<P> Luther's position on ecumenical councils shifted over time, but in 1520 he appealed to the German princes to oppose the papal Church, if necessary with a council in Germany, open and free of the Papacy . After the Pope condemned in Exsurge Domine fifty - two of Luther's theses as heresy, German opinion considered a council the best method to reconcile existing differences . German Catholics, diminished in number, hoped for a council to clarify matters . </P> <P> It took a generation for the council to materialise, partly because of papal reluctance, given that a Lutheran demand was the exclusion of the papacy from the Council, and partly because of ongoing political rivalries between France and Germany and the Turkish dangers in the Mediterranean . Under Pope Clement VII (1523--34), troops of the Catholic Holy Roman Emperor Charles V sacked Papal Rome in 1527, "raping, killing, burning, stealing, the like had not been seen since the Vandals". Saint Peter's Basilica and the Sistine Chapel were used for horses . This, together with the Pontiff's ambivalence between France and Germany, led to his hesitation . </P> <P> Charles V strongly favoured a council, but needed the support of King Francis I of France, who attacked him militarily . Francis I generally opposed a general council due to partial support of the Protestant cause within France, and in 1533 he further complicated matters when suggesting a general council to include both Catholic and Protestant rulers of Europe that would devise a compromise between the two theological systems . This proposal met the opposition of the Pope for it gave recognition to Protestants and also elevated the secular Princes of Europe above the clergy on church matters . Faced with a Turkish attack, Charles held the support of the Protestant German rulers, all of whom delayed the opening of the Council of Trent . </P> <P> In reply to the Papal bull Exsurge Domine of Pope Leo X (1520), Martin Luther burned the document and appealed for a general council . In 1522 German diets joined in the appeal, with Charles V seconding and pressing for a council as a means of reunifying the Church and settling the Reformation controversies . Pope Clement VII (1523--1534) was vehemently against the idea of a council, agreeing with Francis I of France, after Pope Pius II, in his bull Execrabilis (1460) and his reply to the University of Cologne (1463), set aside the theory of the supremacy of general councils laid down by the Council of Constance . </P>

What was decided at the council of trent