On 3 May 1512, the Fifth Lateran Council opened under the authority of Pope Julius II with the participation of fifteen cardinals, two patriarchs, ten archbishops, fifty-six bishops, abbots, generals of religious orders and several ambassadors. Pope Julius would die while the council was in session and Pope Leo X would continue the council until its close on 16 March 1517.
Pope Julius had sworn an oath to call a council, but as he delayed to fulfill this vow some bishops organized their own council in Pisa with the support of French king Louis XII. Seeing this as a rival to his authority, Pope Julius denounced the council and called for his own council at the Lateran. While much of the initial motivation for the Fifth Lateran Council was to condemn the actions and decisions at the earlier council of Pisa, the Fifth Lateran also spoke of the need for reform within the Church – particularly on improving the quality of priests and prohibiting simony in the election of popes. But not much action was taken in this regard.
catholicunderthehood.com 