Ikkō-ikki were rebellious or autonomous groups of people that were formed in several regions of Japan in the 15th-16th centuries; backed up by the power of the Jōdo Shinshū sect of Buddhism, they opposed the rule of governors or daimyō. Mainly consisting of priests, peasants, merchants and local lords who followed the sect, they sometimes associated with non-followers of the sect. They were at first organized to only a small degree; if any single person could be said to have had any influence over them it was Rennyo, the leader of the Jōdo Shinshū Hongan-ji sect at that time. Whilst he may have used the religious fervour of the Ikkō-ikki in the defence of his temple settlements, he was also careful to distance himself from the wider social rebellion of the Ikkō movement as a whole, and from offensive violence in particular.

Daimyo were powerful Japanese magnates, feudal lords who, from the 10th century to the early Meiji period in the middle 19th century, ruled most of Japan from their vast hereditary land holdings. They were subordinate to the shogun and nominally to the emperor and the kuge. In the term, dai (大) means 'large', and myō stands for myōden (名田), meaning 'private land'.