Innocent III was a significant pope who led the Roman Catholic Church from 1198 to 1216. He is known for his strong influence over European politics and his efforts to reform the Church. Innocent III played a key role in the Fourth Crusade, which aimed to reclaim the Holy Land but ultimately resulted in the sack of Constantinople. Innocent III also emphasized the importance of papal authority and sought to strengthen the Church's power. He convened the Fourth Lateran Council in 1215, which addressed various issues, including the administration of the sacraments and the need for clerical reform. His papacy marked a high point in the medieval Church's influence.