Tiglath-Pileser I was a king of Assyria during the Middle Assyrian period. According to Georges Roux, Tiglath-Pileser was "one of the two or three great Assyrian monarchs since the days of Shamshi-Adad I". He was known for his "wide-ranging military campaigns, his enthusiasm for building projects, and his interest in cuneiform tablet collections". Under him, Assyria became the leading power of the Ancient Near East, a position the kingdom largely maintained for the next five hundred years. He expanded Assyrian control into Anatolia and Syria, and to the shores of the Mediterranean Sea. From his surviving inscriptions, he seems to have carefully cultivated a fear of himself in his subjects and in his enemies alike.

The Middle Assyrian Empire was the third stage of Assyrian history, covering the history of Assyria from the accession of Ashur-uballit I c. 1365 BC and the rise of Assyria as a territorial kingdom to the death of Ashur-dan II in 912 BC. The Middle Assyrian Empire was Assyria's first true period of ascendancy as an empire, although Assyrian kings had existed from perhaps as early as the 25th century BC, and from the 21st century BC Assyria had controlled trading colonies in Anatolia and had economic and military influence in Southern Mesopotamia, and from the late 19th century BC had been an integral part of the "Empire of Shamsi-Adad", sometimes called the Old Assyrian Empire. Though the empire experienced successive periods of expansion and decline, it remained the dominant power of Mesopotamia and often the entirety of West Asia throughout the period. In terms of Assyrian history, the Middle Assyrian period was marked by important social, political and religious developments, including the rising prominence of both the Assyrian king and the Assyrian national deity Ashur.