Synod of Worms (1076)

It was intended to agree a condemnation of Pope Gregory VII, and Henry's success in achieving this outcome marked the beginning of the Investiture Controversy.

In 1067 Archbishop Guido of Milan, facing the rising forces of the pataria reformers in the city, gave up his see.

Not until Henry IV again interfered in the Milan struggles and appointed Tebald da Castiglione archbishop, as well as bishops of Spoleto and Fermo, both on papal territory, the conflict escalated.

Under pressure, the Salian king allied with the German episcopacy, benefitting from their hostile stance on the Gregorian Reform and a centralisation of church authority.

In October, the German princes gathered at Trebur and ultimately asked the king to reconcile with the Pope.