The famous struggle characterized by the conflict between the Catholic Church and European monarchs is known as the Investiture Controversy. This power struggle lasted from the late 11th century to the early 12th century and revolved around the appointment of bishops and the control of church lands. The conflict primarily pitted Pope Gregory VII against Emperor Henry IV, culminating in events like Henry's excommunication and subsequent public penance. The controversy underscored the tension between ecclesiastical and secular authority, shaping the political landscape of medieval Europe and influencing the relationship between church and state.