The Byzantine calendar called "Creation Era of Constantinople" or "Era of the World", was the calendar used by the Eastern Orthodox Church from c. 691 to 1728 in the Ecumenical Patriarchate. It was the official calendar of the Byzantine Empire from 988 to 1453, of Kievan Rus' and Russia from c. 988 to 1700. Since "Byzantine" is a historiographical term, the original name uses the noun "Roman" as it was how the Eastern Roman Empire continued calling itself; the calendar was based on the Julian calendar, except that the year started on 1 September and the year number used an Anno Mundi epoch derived from the Septuagint version of the Bible. It placed the date of creation at 5509 years before the Incarnation, was characterized by a certain tendency, a tradition among Jews and early Christians to number the years from the calculated foundation of the world, its Year One, marking the supposed date of creation, was September 1, 5509 BC, to August 31, 5508 BC. It is not known when; the first appearance of the term is in the treatise of a certain "monk and priest", who mentions all the main variants of the "World Era" in his work.
Georgios argues that the main advantage of the World era is the common starting point of the astronomical lunar and solar cycles, of the cycle of indictions, the usual dating system in Byzantium since the 6th century. He already regards it as the most convenient for the Easter computus. Complex calculations of the 19-year lunar and 28-year solar cycles within this world era allowed scholars to discover the cosmic significance of certain historical dates, such as the birth or the crucifixion of Jesus; this date underwent minor revisions before being finalized in the mid-7th century, although its precursors were developed c. AD 412. By the second half of the 7th century, the Creation Era was known in Western Europe, at least in Great Britain. By the late 10th century around AD 988, when the era appears in use on official government records, a unified system was recognized across the Eastern Roman world; the era was calculated as starting on September 1, Jesus was thought to have been born in the year 5509 since the creation of the world.
Historical time was thus calculated from the creation, not from Christ's birth, as in the west after the Anno Domini system was adopted between 6th and 9th centuries. The Eastern Church avoided the use of the Anno Domini system of Dionysius Exiguus, since the date of Christ's birth was debated in Constantinople as late as the 14th century. Otherwise the Byzantine calendar was identical to the Julian Calendar except that: the names of the months were transcribed from Latin into Greek; the leap day of the Byzantine calendar was obtained in an identical manner to the bissextile day of the original Roman version of the Julian calendar, by doubling the sixth day before the calends of March, i.e. by doubling 24 February. The Byzantine World Era was replaced in the Orthodox Church by the Christian Era, utilized by Patriarch Theophanes I Karykes in 1597, afterwards by Patriarch Cyril Lucaris in 1626, formally established by the Church in 1728. Meanwhile, as Russia received Orthodox Christianity from Byzantium, she inherited the Orthodox Calendar based on the Byzantine Era.
After the collapse of the Byzantine Empire in 1453, the era continued to be used by Russia, which witnessed millennialist movements in Moscow in AD 1492. It was only in AD 1700 that the Byzantine World Era in Russia was changed to the Julian Calendar by Peter the Great, it still forms the basis of traditional Orthodox calendars up to today. September AD 2000 began the year 7509 AM; the earliest extant Christian writings on the age of the world according to the Biblical chronology are by Theophilus, the sixth bishop of Antioch from the Apostles, in his apologetic work To Autolycus, by Julius Africanus in his Five Books of Chronology. Both of these early Christian writers, following the Septuagint version of the Old Testament, determined the age of the world to have been about 5,530 years at the birth of Christ. Ben Zion Wacholder points out that the writings of the Church Fathers on this subject are of vital significance, in that through the Christian chronographers a window to the earlier Hellenistic biblical chronographers is preserved: An immense intellectual effort was expended during the Hellenistic period by both Jews and pagans to date creation, the flood, building of the Temple...
In the course of their studies, men such as Tatian of Antioch, Clement of Alexandria, Hippolytus of Rome
The Islamic, Muslim, or Hijri calendar is a lunar calendar consisting of 12 lunar months in a year of 354 or 355 days. It is used to determine the proper days of Islamic holidays and rituals, such as the annual period of fasting and the proper time for the pilgrimage to Mecca; the civil calendar of all countries where the religion is predominantly Muslim is the Gregorian calendar. Notable exceptions to this rule are Afghanistan, which use the Solar Hijri calendar. Rents and similar regular commitments are paid by the civil calendar; the Islamic calendar employs the Hijri era whose epoch was established as the Islamic New Year of 622 AD/CE. During that year and his followers migrated from Mecca to Yathrib and established the first Muslim community, an event commemorated as the Hijra. In the West, dates in this era are denoted AH in parallel with the Christian and Jewish eras. In Muslim countries, it is sometimes denoted as H from its Arabic form. In English, years prior to the Hijra are reckoned as BH.
The current Islamic year is 1440 AH. In the Gregorian calendar, 1440 AH runs from 11 September 2018 to 30 August 2019. For central Arabia Mecca, there is a lack of epigraphical evidence but details are found in the writings of Muslim authors of the Abbasid era. Inscriptions of the ancient South Arabian calendars reveal the use of a number of local calendars. At least some of these South Arabian calendars followed the lunisolar system. Both al-Biruni and al-Mas'udi suggest that the ancient Arabs used the same month names as the Muslims, though they record other month names used by the pre-Islamic Arabs; the Islamic tradition is unanimous in stating that Arabs of Tihamah and Najd distinguished between two types of months and forbidden months. The forbidden months were four months during which fighting is forbidden, listed as Rajab and the three months around the pilgrimage season, Dhu al-Qa‘dah, Dhu al-Hijjah, Muharram. Information about the forbidden months is found in the writings of Procopius, where he describes an armistice with the Eastern Arabs of the Lakhmid al-Mundhir which happened in the summer of 541 AD/CE.
However, Muslim historians do not link these months to a particular season. The Qur'an links the four forbidden months with Nasī’, a word that means "postponement". According to Muslim tradition, the decision of postponement was administered by the tribe of Kinanah, by a man known as the al-Qalammas of Kinanah and his descendants. Different interpretations of the concept of Nasī’ have been proposed; some scholars, both Muslim and Western, maintain that the pre-Islamic calendar used in central Arabia was a purely lunar calendar similar to the modern Islamic calendar. According to this view, Nasī’ is related to the pre-Islamic practices of the Meccan Arabs, where they would alter the distribution of the forbidden months within a given year without implying a calendar manipulation; this interpretation is supported by Arab historians and lexicographers, like Ibn Hisham, Ibn Manzur, the corpus of Qur'anic exegesis. This is corroborated by an early Sabaic inscription, where a religious ritual was "postponed" due to war.
According to the context of this inscription, the verb ns'’ has nothing to do with intercalation, but only with moving religious events within the calendar itself. The similarity between the religious concept of this ancient inscription and the Qur'an suggests that non-calendaring postponement is the Qur'anic meaning of Nasī’; the Encyclopaedia of Islam concludes "The Arabic system of can only have been intended to move the Hajj and the fairs associated with it in the vicinity of Mecca to a suitable season of the year. It was not intended to establish a fixed calendar to be observed." The term "fixed calendar" is understood to refer to the non-intercalated calendar. Others concur that it was a lunar calendar, but suggest that about 200 years before the Hijra it was transformed into a lunisolar calendar containing an intercalary month added from time to time to keep the pilgrimage within the season of the year when merchandise was most abundant; this interpretation was first proposed by the medieval Muslim astrologer and astronomer Abu Ma'shar al-Balkhi, by al-Biruni, al-Mas'udi, some western scholars.
This interpretation considers Nasī’ to be a synonym to the Arabic word for "intercalation". The Arabs, according to one explanation mentioned by Abu Ma'shar, learned of this type of intercalation from the Jews; the Jewish Nasi was the official. Some sources say that the Arabs followed the Jewish practice and intercalated seven months over nineteen years, or else that they intercalated nine months over 24 years. Postponement of one ritual in a particular circumstance does not imply alteration of the sequence of months, scholars agree that this did not happen. Al-Biruni says this did not happen, the festivals were kept within their season by intercalation every second or third year of a month between Dhu al-Hijjah and Muharram, he says that, in terms of the fixed calendar, not introduced until 10 AH, the first intercalation was, for example, of a month between Dhu al-Hijjah and Muharram, the second of a month between Muharram and Safar, the third of a month between Safar and Rabi'I, so on. The intercalations were arranged.
The notice of interca
The 8th century is the period from 701 to 800 in accordance with the Julian calendar in the Common Era. The coast of North Africa and the Iberian Peninsula come under Islamic Arab domination; the westward expansion of the Umayyad Empire was famously halted at the Siege of Constantinople by the Byzantine Empire and the Battle of Tours by the Franks. The tide of Arab conquest came to an end in the middle of the 8th century. In Europe, late in the century, the Vikings, seafaring peoples from Scandinavia, begin raiding the coasts of Europe and the Mediterranean, go on to found several important kingdoms. In Asia, the Pala Empire is founded in Bengal; the Tang dynasty reaches its pinnacle under Chinese Emperor Xuanzong. The Nara period begins in Japan. Estimated century in which the poem Beowulf is composed. Classical Maya civilization begins to decline; the first Serbian state is formed at the beginning of the century. Borobodur, the famous Indonesian Buddhist structure, begins construction as a non-Buddhist shrine.
Buddhist Jataka stories are translated into Arabic as Kalilag and Damnag. An account of Buddha's life is translated into Greek by Saint John of Damascus, circulated to Christians as the story of Barlaam and Josaphat. Height of the Classic period in pre-Columbian Maya civilization history. Śāntideva, a Buddhist monk at Nalanda Monastery in India, composes the famous Bodhicharyāvatāra, or Guide to the Bodhisattva's Way of Life. The height of the Giant Wild Goose Pagoda in Xian, China is extended by 5 stories. 701: The Taihō Code is enacted in late Asuka period Japan. 705: Overthrow of Empress Wu Zetian, the reign of China's first and only sole-ruling empress ends. 705: Justinian II is forced to give the title Caesar of Byzantium to the Bulgarian Emperor Tervel. The Byzantine Empire begins to pay annual tributes to Bulgaria. 708 – 711: The Bulgarians defeat Justinian II at the battle of Anchiallus. Arab armies occupied Sindh. 710: Empress Genmei moves the capital to Heijō-kyū, initiating the Nara period of Japan.
711: Palenque is conquered by Toniná. 711: Tariq ibn Ziyad crosses the Straits of Gibraltar. With the creation of Al-Andalus, most of the Iberian Peninsula is conquered by Arab and Berber Muslims, thus ending the Visigothic rule, beginning eight centuries of Muslim rule. 712: Liutprand, King of the Lombards begins his reign. C. 712: Metropolitan episcopal see is established by the Church of the East in Chinese capital of Chang'an. 712 – 756: Emperor Xuanzong reigned, the time was considered one of China's high points. 712 – 740: Caliphate campaigns in India 713: Death of Dajian Huineng and last Patriarch of Chán Buddhism. 717 – 718: Siege of Constantinople. The Bulgarians and the Byzantines decisively defeat the invading Arabs, thus halting the Arab advance toward Europe. 718: Sri Indravarman King of Srivijaya send a letter to the Caliph Umar bin Abdul Aziz of the Umayyad Caliphate in Damascus, signing early ancient Indonesian official contact with Islamic world in the Middle East. 726: Byzantine Emperor Leo III the Isaurian destroys the icon of Christ above the Chalke Gate in the capital city of Constantinople, beginning the first phase of the Byzantine Iconoclasm.
731: Bede completes his Historia ecclesiastica gentis Anglorum. 732: Battle of Tours. Near Poitiers, leader of the Franks Charles Martel and his men defeat a large army of Moors under the governor of Cordoba, Abdul Rahman Al Ghafiqi, killed during the battle; the Battle of Tours halts the advance of Islam into Western Europe and establishes a balance of power between Western Europe and the Byzantine Empire. 732: The Sanjaya dynasty is founded around this time according to the Canggal inscription. 738: Quiriguá declares independence from Copan 740: Battle of Akroinon. Byzantines win their first large-scale victory in a pitched battle against the Arabs. 742: For the municipal census of the Tang-dynasty Chinese capital city Chang'an and its metropolitan area of Jingzhou Fu, the New Book of Tang records that in this year there were 362,921 registered families with 1,960,188 persons. 748: The Chinese Buddhist monk Jian Zhen writes in his Yue Jue Shu of the international sea traffic coming to Guangzhou, ships from Borneo, Sri Lanka and others bringing tons of goods.
750: The last Umayyad Caliph Marwan II is overthrown and executed by the first Abbasid Caliph, Abu al-Abbas al-Saffah. The Caliphate is moved to Baghdad which would develop into a centre of trade and culture; the Ghana Empire begins in western Africa. Mid-8th century - Great Wild Goose Pagoda at Ci'en Temple, Xi'an, Shanxi, is rebuilt. C. mid-8th century - Camel Carrying a Group of Musicians, from a tomb near Xi'an, Shanxi, is made. Tang dynasty, it is now kept at Museum of Beijing. 751: Arabian armies defeat Chinese Tang dynasty troops in the Battle of Talas, in the high Pamirs near Samarkand, conquer Central Asia completely. 752: The Hindu Medang kingdom flourishes and declines. 755 – 763: The An Shi Rebellion devastates China during the mid Tang dynasty. 757: King Offa of Mercia becomes dominant ruler in England. 758: Arab and Persian pirates and travelers burn and loot the Chinese city of Guangzhou, while the Tang Dynasty authorities shut the port down for the next five decades. 760: The construction of Borobudur started.
768: Pepin dies. 770's – 780's: Java launched series of naval raids on ports of Dai Viet and Cambodia. The naval raids was launched by Sailendran-Srivijayan Maharaja
The 10th century was the period from 901 to 1000 in accordance with the Julian calendar, the last century of the 1st millennium. In China the Song dynasty was established; the Muslim World experienced a cultural zenith in al-Andalus under the Caliphate of Córdoba. Additionally, it was the zenith for the Bulgarian Empires. Medievalist and historian of technology Lynn White said that "to the modern eye, it is nearly the darkest of the Dark Ages", but concluded that "... if it was dark, it was the darkness of the womb." Helen Waddell wrote that the 10th century was that which "in the textbooks disputes with the seventh the bad eminence, the nadir of the human intellect." In the 15th century, Lorenzo Valla described it as the Century of Lead and Iron and Cardinal Baronius as the Leaden Century or Iron Century. According to one estimate, the tenth century saw fewer deaths in war than any other century since 3000 BC; the beginning of the Medieval Warm Period The Byzantine empire reaches the height of its military and economic strength c. 909: The Fatimid Caliphate arises in eastern Algeria.
C. 948: The Nri Kingdom in what is now Southeastern Nigeria starts. C. 980: Al-Azhar University is established in Cairo by the Fatimid dynasty. The Christian Nubian kingdom reaches its peak of prosperity and military power Collapse of the central lowland Maya civilization. Post-Classic Maya period begins. Chichen Itza becomes a regional capital on the Yucatán Peninsula Rise of the Toltecs in Mexico Golden age of the Ancestral Puebloans The Mississippian culture begins in present-day Southern United States In 987 Ah Mekat Tutul Xiu unified Uxmal and Chichen Itza founding The League of Mayapan. Khazar kingdom is attacked and defeated by Kievan Rus Buddhist temple construction commences at Bagan, Burma In 907, Zhu Quanzhong deposes Emperor Ai of Tang and establishes a new Later Liang dynasty. In 907, Sumbing volcano erupts, according to Rukam inscription. In 907, King Balitung creates the Mantyasih inscription containing the list of Medang kings, moves the capital from Mamrati to Poh Pitu, expands Prambanan temple.
In 910, Parantaka I of the Chola Dynasty drives out the Pandyan from southern India into Lanka, which he eventually conquers. In 914, The Warmadewa dynasty rules Bali. In 919, the first use of gunpowder in battle occurs with the Chinese Battle of Langshan Jiang, where the Wuyue naval fleet under Qian Yuanguan defeats the Wu fleet. Qian had used flamethrowers ignited by gunpowder fuses to burn the Wu fleet. In 928, Ziyarid dynasty is established in northern Iran. In 928, During the reign of King Wawa, the capital of Medang Kingdom in Mataram is devastated by the massive eruption of Mount Merapi. In 929, Mpu Sindok moves the seat of power of the Medang Kingdom from Mataram in Central Java to Tamwlang in East Java and establishes Isyana Dynasty; the shift is as a result of the eruption of Mount Merapi and/or invasion from Srivijaya. In 930s, Persian Shia Buyid dynasty establishes and controls central and western part of Iran as well as most of Iraq. In 936, Goryeo Dynasty unifies Later Three Kingdoms of Korea.
In 937, Mpu Sindok moves the capital again from Tamwlang to Watugaluh, both near bank of Brantas River in modern Jombang in East Java. In 960, Zhao Kuangyin establishes Song dynasty. In 960 Seljuks convert to Islam. In 975, Ghaznavids dynasty, as the first Turk Sultanate, was established in Central Asia. In 979, Song dynasty reunites China. In 980's, Dynastic marriage between princess Mahendradatta of Javanese Isyanas and king Udayana of Balinese Warmadewas. Coastal cities on the Malay Peninsula are the seed for the first recorded Malay kingdoms In 990, King Dharmawangsa of Medang kingdom launches a naval invasion on Palembang in an unsuccessful attempt to conquer Srivijaya. In 990, son of King Udayana and Queen Mahendradatta was born in Bali. In 996, Dharmawangsa commissioned the translation of the Mahabharata into Old Javanese. In 999, Samanid dynasty was conquered by Ghaznavids. Viking groups settle in northern France 907: Loire Vikings overrun Brittany; the Norse become Normans The Hungarian army destroys the Bavarian forces under duke Liutpold and king Louis the Child in the Battle of Pressburg.
All the German force is annihilated. 911: Rollo granted County of Rouen by France: official foundation of Normandy. Foundation of Cluny, first federated monastic order Emperor Simeon the Great solidifies the First Bulgarian Empire as one of the most powerful states in Europe In 917 the Bulgarians destroyed the Byzantine army in the Battle of Anchialus, one of the bloodiest battles in the Middle Ages 927: official recognition of the first independent national Church in Europe, the Bulgarian Patriarchate 927: Kingdom of England becomes a unified state. C. 936: Gorm the Old becomes the first recognized king of Denmark, thus the Danish Monarchy is founded. 936: Alan II, with support from Æthelstan, commences the reconquest of Brittany. 955 The Battle of Lechfeld sees a decisive victory for Otto I the Great, King of the Germans, over the Hungarian harka Bulcsú and the chieftains Lél and Súr. Incursions of Magyar cavalry throughout Western Europe Mieszko I, first duke of Poland, baptised a Christian in 966 Collapse of Great Moravia The medieval Croatian state becomes a unified kingdom under King Tomislav Swedish influence extends to the Black Sea Volodymyr I, Prince of Kievan Rus', baptised a Christian in 988 Reindeer and bears become extinct in Britain Lions become extinct in Europe
Balinese saka calendar
The Balinese saka calendar is one of two calendars used on the Indonesian island of Bali. Unlike the 210-day pawukon calendar, it is based on the phases of the Moon, is the same length as the Gregorian year. Based on a lunar calendar, the saka year comprises sasih, of 30 days each. However, because the lunar cycle is shorter than 30 days, the lunar year has a length of 354 or 355 days, the calendar is adjusted to prevent it losing synchronization with the lunar or solar cycles; the months are adjusted by allocating two lunar days to one solar day every 9 weeks. This day is called ngunalatri, Sanskrit for "minus one night". To stop the Saka from lagging behind the Gregorian calendar – as happens with the Islamic calendar, an extra month, known as an intercalary month, is added after the 11th month, or after the 12th month; the length of these months is calculated according to the normal 63-day cycle. An intercalary month is added whenever necessary to prevent the final day of the 7th month, known as Tilem Kapitu, from falling in the Gregorian month of December.
The names the twelve months are taken from a mixture of Old Balinese and Sanskrit words for 1 to 12, are as follows: Kasa Karo Katiga Kapat Kalima Kanem Kapitu Kawalu Kasanga Kadasa Jyestha SadhaEach month begins the day after a new moon and has 15 days of waxing moon until the full moon 15 days of waning, ending on the new moon. Both sets of days are numbered 1 to 15; the first day of the year is the day after the first new moon in March. Note, that Nyepi falls on the first day of Kadasa, that the years of the Saka era are counted from that date; the calendar is 78 years behind the Gregorian calendar, is calculated from the beginning of the Saka Era in India. It is used alongside the 210-day Balinese pawukon calendar, Balinese festivals can be calculated according to either year; the Indian saka calendar was used for royal decrees as early as the ninth century CE. The same calendar was used in Java until Sultan Agung replaced it with the Javanese calendar in 1633; the Balinese Hindu festival of Nyepi, the day of silence, marks the start of the Saka year.
Tilem Kepitu, the last day of the 7th month, is known as Siva Ratri, is a night dedicated to the god Shiva. Devotees stay up all meditate. There are another 24 ceremonial days in the Saka year celebrated at Purnama. Eiseman, Fred B. Jr, Bali: Sekalia and Niskala Volume I: Essays on Religion and Art pp 182–185, Periplus Editions, 1989 ISBN 0-945971-03-6 Haer, Debbie Guthrie. ISBN 981 3018 496 Hobart, Angela. ISBN 0 631 17687 X Ricklefs, M. C.
The traditional China calendar, or Former Calendar, Traditional Calendar or Lunar Calendar, is a lunisolar calendar which reckons years and days according to astronomical phenomena. It is defined by GB/T 33661-2017, "Calculation and promulgation of the Chinese calendar", issued by the Standardisation Administration of China on 12 May 2017. Although modern day China uses the Gregorian calendar, the traditional Chinese calendar governs holidays in China and in overseas Chinese communities, it lists the dates of traditional Chinese holidays and guides people in selecting auspicious days for weddings, moving, or starting a business. Like Chinese characters, variants of this calendar are used in different parts of the Chinese cultural sphere. Korea and the Ryukyu Islands adopted the calendar, it evolved into Korean and Ryukyuan calendars; the main difference from the traditional Chinese calendar is the use of different meridians, which leads to some astronomical events—and calendar events based on them—falling on different dates.
The traditional Japanese calendar derived from the Chinese calendar, but its official use in Japan was abolished in 1873 as part of reforms after the Meiji Restoration. Calendars in Mongolia and Tibet have absorbed elements of the traditional Chinese calendar, but are not direct descendants of it. Days begin and end at midnight, months begin on the day of the new moon. Years begin on the second new moon after the winter solstice. Solar terms govern the end of each month. Written versions in ancient China included stems and branches of the year and the names of each month, including leap months as needed. Characters indicated whether a month was short; the traditional Chinese calendar was developed between 771 and 476 BC, during the Spring and Autumn period of the Eastern Zhou dynasty. Before the Zhou dynasty, solar calendars were used. One version of the solar calendar is the five-elements calendar. A 365-day year was divided into five phases of 73 days, with each phase corresponding to a Day 1 Wu Xing element.
A phase began followed by six 12-day weeks. Each phase consisted of two three-week months. Years began followed by a bǐngzǐ day and a 72-day fire phase. Other days were tracked using the Yellow River Map. Another version is a four-quarters calendar. Weeks were ten days long, with one month consisting of three weeks. A year had 12 months, with a ten-day week intercalated in summer as needed to keep up with the tropical year; the 10 Heavenly Stems and 12 Earthly Branches were used to mark days. A third version is the balanced calendar. A year was 365.25 days, a month was 29.5 days. After every 16th month, a half-month was intercalated. According to oracle bone records, the Shang dynasty calendar was a balanced calendar with 12 to 14 months in a year; the first lunisolar calendar was the Zhou calendar, introduced under the Zhou dynasty. This calendar set the beginning of the year at the day of the new moon before the winter solstice, it set the shàngyuán as the winter solstice of a dīngsì year, making the year it was introduced around 2,758,130.
Several competing lunisolar calendars were introduced by states fighting Zhou control during the Warring States period. The state of Lu issued its own Lu calendar. Jin issued the Xia calendar in AD 102, with a year beginning on the day of the new moon nearest the March equinox. Qin issued the Zhuanxu calendar, with a year beginning on the day of the new moon nearest the winter solstice. Song's Yin calendar began its year on the day of the new moon after the winter solstice; these calendars are known as the six ancient calendars, or quarter-remainder calendars, since all calculate a year as 365 1⁄4 days long. Months begin on the day of the new moon, a year has 12 or 13 months. Intercalary months are added to the end of the year; the Qiang and Dai calendars are modern versions of the Zhuanxu calendar, used by mountain peoples. After Qin Shi Huang unified China under the Qin dynasty in 221 BC, the Qin calendar was introduced, it followed most of the rules governing the Zhuanxu calendar, but the month order was that of the Xia calendar.
The intercalary month, known as the second Jiǔyuè, was placed at the end of the year. The Qin calendar was used into the Han dynasty. Emperor Wu of Han r. 141 – 87 BC introduced reforms halfway through his reign. His Taichu Calendar defined a solar year as 365 385⁄1539 days, the lunar month was 29 43⁄81 days; this calendar introduced the 24 solar terms. Solar terms were paired, with the 12 combined periods known as climate terms; the first solar term of the period was known as a pre-climate, the second was a mid-climate. Months were named for the mid-climat
Thomas the Slav
Thomas the Slav was a 9th-century Byzantine military commander, most notable for leading a wide-scale revolt in 821–23 against Emperor Michael II the Amorian. An army officer of Slavic origin from the Pontus region, Thomas rose to prominence, along with the future emperors Michael II and Leo V the Armenian, under the protection of general Bardanes Tourkos. After Bardanes' failed rebellion in 803, Thomas fell into obscurity until Leo V's rise to the throne, when Thomas was raised to a senior military command in central Asia Minor. After the murder of Leo and usurpation of the throne by Michael the Amorian, Thomas revolted, claiming the throne for himself. Thomas secured support from most of the themes and troops in Asia Minor, defeated Michael's initial counter-attack and concluded an alliance with the Abbasid Caliphate. After winning over the maritime themes and their ships as well, he crossed with his army to Europe and laid siege to Constantinople; the imperial capital withstood Thomas's attacks by land and sea, while Michael II called for help from the Bulgarian ruler khan Omurtag.
Omurtag attacked Thomas's army, but although repelled, the Bulgarians inflicted heavy casualties on Thomas's men, who broke and fled when Michael took to the field a few months later. Thomas and his supporters sought refuge in Arcadiopolis, where he was soon blockaded by Michael's troops. In the end, Thomas's supporters surrendered him in exchange for a pardon, he was executed. Thomas's rebellion was one of the largest in the Byzantine Empire's history, but its precise circumstances are unclear due to competing historical narratives, which have come to include claims fabricated by Michael to blacken his opponent's name. Various motives and driving forces have been attributed to Thomas and his followers; as summarized by the Oxford Dictionary of Byzantium, "Thomas's revolt has been variously attributed to a reaction against Iconoclasm, a social revolution and popular uprising, a revolt by the Empire's non-Greek ethnic groups, Thomas's personal ambitions, his desire to avenge Leo V." Its effects on the military position of the Empire vis-à-vis the Arabs, are disputed.
The 11th-century Theophanes Continuatus states that Thomas was descended from South Slavs resettled in Asia Minor by successive Byzantine emperors, while the 10th-century chronicler Genesios calls him "Thomas from Lake Gouzourou, of Armenian race". Most modern scholars support his Slavic descent and believe his birthplace to have been near Gaziura in the Pontus. Hence his epithet of "the Slav", applied to him only in modern times. Nothing is known about his family and early life, except that his parents were poor and that Thomas himself had received no education. Given that he was between 50 and 60 years old at the time of the rebellion, he was born around 760. Two different accounts of Thomas's life are recounted in both Genesios and Theophanes Continuatus. According to the first account, Thomas first appeared in 803 accompanying general Bardanes Tourkos, pursued a military career until launching his revolt in late 820. In the second version, he came to Constantinople as a poor youth and entered the service of a man with the high court rank of patrikios.
Discovered trying to commit adultery with his master's wife, Thomas fled to the Arabs in Syria, where he remained for 25 years. Pretending to be the murdered emperor Constantine VI, he led an Arab-sponsored invasion of Asia Minor, but was defeated and punished. Classical and Byzantine scholar J. B. Bury tried to reconcile the two narratives, placing Thomas's flight to the Abbasid Caliphate at around 788 and having him return to Byzantine service before 803, while the Russian scholar Alexander Vasiliev interpreted the sources as implying that Thomas fled to the Caliphate at Constantine VI's deposition in 797, that his participation in Bardanes's revolt must be discounted entirely; the second version of Thomas's story is explicitly preferred by Genesios and Theophanes Continuatus, is the only one recorded in 9th-century sources, namely the chronicle of George the Monk and the Life of Saints David and George of Lesbos. The French Byzantinist Paul Lemerle came to consider it an unreliable tradition created by his rival Michael II to discredit Thomas, rejected it altogether, preferring to rely on the first account alone.
Most modern scholars follow him in this interpretation. The first tradition relates that Thomas served as a spatharios to Bardanes Tourkos, the monostrategos of the eastern themes, who in 803 rose in rebellion against Emperor Nikephoros I. Alongside Thomas were two other young spatharioi in Bardanes's retinue, who formed a fraternal association: Leo the Armenian, the future Leo V, Michael the Amorian, the future Michael II. According to a hagiographic tradition, before launching his revolt, Bardanes, in the company of his three young protégés, is said to have visited a monk near Philomelion, reputed to foresee the future; the monk predicted what would indeed happen: that Bardanes's revolt would fail, that Leo and Michael would both become emperors, that Thomas would be acclaimed emperor and killed. When Bardanes did in fact rise up, he failed to win any widespread support. Leo and Michael soon abandoned him and defected to the imperial camp and were rewarded with senior military posts. Thomas alone remained loyal to Bardanes until his surrender.
In the aftermath of Bardanes's failure, Thomas disappears from the sources for ten years. Bury suggests that he fled