On 24 January 1076, Henry IV ⓘ convened a synod of German bishops at Worms, where the assembly formally declared Gregory VII ⓘ deposed.

The conflict arose from Gregory’s programme of church reform and his opposition to lay investiture, the practice by which secular rulers appointed bishops and abbots. Henry and many imperial bishops rejected Gregory’s authority and accused him of unlawfully occupying the papal office.

In response to the synod’s declaration, Gregory VII excommunicated Henry IV and released his subjects from their oaths of loyalty. The confrontation marked a decisive escalation in the Investiture Controversy ⓘ, the long struggle between papal and imperial authority in medieval Europe.