This great quarrel, what became known as the Investiture Struggle, was a protracted conflict with secular authorities for control of Church offices, where Gregory was merely the first in a long line of popes who followed his lead.3 The process he began culminated in 1122 in the Concordat of Worms (during the reign of the French pope Calixtus II, 11191124), whereby the emperor agreed to give up spiritual investiture and allow free ecclesiastical elections.
