Fourth Lateran Council in the context of "Trinitarianism"

Papal income tax was first levied in 1199 by Pope Innocent III, originally requiring all Catholic clergy to pay one-fortieth of their ecclesiastical income annually in support of the Crusades. The second income tax was not levied until the Fourth Lateran Council in 1215, and constituted only a triennial twentieth.

This precedent was frequently continued by the successors of Innocent III, enforced by ecclesiastical censure, by sequestration, and frequently by the use of force. The first time the tax was imposed, contributors were promised that a quarter of the penances would be rebated if payments were made willingly and honestly; the second time, non-compliance was simply threatened with excommunication. On a few occasions popes convoked a general council before imposing an income tax, but more often imposed the tax solely on their own authority.

Pope Innocent III (Latin: Innocentius III; born Lotario de' Conti di Segni; 22 February 1161 – 16 July 1216) was the head of the Catholic Church and sovereign of the Papal States from 8 January 1198 until his death in 1216.

Pope Innocent was one of the most powerful and influential of the medieval popes. He exerted a wide influence over the Christian states of Europe, claiming supremacy over all of Europe's kings. He was central in supporting the Catholic Church's reforms of ecclesiastical affairs through his decretals and the Fourth Lateran Council. This resulted in a considerable refinement of Western canon law. He is furthermore notable for using interdict and other censures to compel princes to obey his decisions, although these measures were not uniformly successful.