The Second Council of Lyon was an important assembly of the Roman Catholic Church held in 1274. Convened by Pope Gregory X, the council aimed to address various issues, including the reunification of the Eastern Orthodox Church and the Roman Catholic Church. It also focused on reforming church practices and improving the administration of the church. During the council, significant decisions were made, including the establishment of a new crusade to reclaim the Holy Land. The council's decrees emphasized the importance of papal authority and sought to strengthen the church's influence in Europe. However, the reunification efforts were ultimately unsuccessful.