<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> <P> Pope Paul III (1534--1549), seeing that the Protestant Reformation was no longer confined to a few preachers, but had won over various princes, particularly in Germany, to its ideas, desired a council . Yet when he proposed the idea to his cardinals, it was almost unanimously opposed . Nonetheless, he sent nuncios throughout Europe to propose the idea . Paul III issued a decree for a general council to be held in Mantua, Italy, to begin on 23 May 1537 . Martin Luther wrote the Smalcald Articles in preparation for the general council . The Smalcald Articles were designed to sharply define where the Lutherans could and could not compromise . The council was ordered by the Emperor and Pope Paul III to convene in Mantua on 23 May 1537 . It failed to convene after another war broke out between France and Charles V, resulting in a non-attendance of French prelates . Protestants refused to attend as well . Financial difficulties in Mantua led the Pope in the autumn of 1537 to move the council to Vicenza, where participation was poor . The Council was postponed indefinitely on 21 May 1539 . Pope Paul III then initiated several internal Church reforms while Emperor Charles V convened with Protestants at an imperial diet in Regensburg, to reconcile differences . Unity failed between Catholic and Protestant representatives "because of different concepts of Church and justification". </P> <P> However, the council was delayed until 1545 and, as it happened, convened right before Luther's death . Unable, however, to resist the urging of Charles V, the pope, after proposing Mantua as the place of meeting, convened the council at Trent (at that time ruled by a prince - bishop under the Holy Roman Empire), on 13 December 1545; the Pope's decision to transfer it to Bologna in March 1547 on the pretext of avoiding a plague failed to take effect and the Council was indefinitely prorogued on 17 September 1549 . None of the three popes reigning over the duration of the council ever attended, which had been a condition of Charles V. Papal legates were appointed to represent the Papacy . </P>

Four decrees of the council of trent were