Final answer:
Pope Gregory VII was the eleventh-century leader who actively denounced simony and refused financial incentives for the appointment of bishops, thereby initiating significant reforms in the Catholic Church.
Step-by-step explanation:
The Eleventh-Century Emperor Who Denounced Simony
The eleventh-century emperor who denounced simony and refused to accept money or gifts when appointing bishops was Pope Gregory VII.
As a part of the church reform, he banned the practice of simony, which is the selling of church offices. This was a significant move against the corruption affecting the Catholic Church at the time. Pope Gregory VII actively fought against simony and even excommunicated Holy Roman Emperor Henry IV, who continued the practice. His actions were pivotal in the investiture controversy, leading to significant changes in the relationship between the church and secular authorities.