Council of Siena

In the Catholic Church, the Council of Siena (1423–1424) marked a somewhat inconclusive stage in the Conciliar movement that was attempting reforms in the Church. If it had continued, it would have qualified as an ecumenical council. In the official List of ecumenical councils, the Council of Siena is no longer listed, as the conciliarism expressed there was later branded as a heresy.

According to the terms of the Council of Constance calling for periodic ecumenical councils to discuss church policies, Pope Martin V convened a council at Pavia, which was hardly inaugurated on 23 April 1423, when plague broke out at Pavia and the council was hastily adjourned to Siena.

At Siena, the procedure of the Council followed that established at Constance. Right at the start, certain formalities of the safe conducts issued by the city for the members of the Council were the cause of jurisdictional friction with papal prerogatives. Nevertheless, on the eighth of November four decrees were published, all of them directed against easy targets: against the followers of the heretical reformers, Jan Hus, recently burnt at the stake at the Council of Constance despite a promise of safe conduct, and against the English followers of John Wycliffe, who claimed that the highest authority was the Bible; against the followers of the schismatic Antipope Benedict XIII; a decree postponing the negotiations with the Greeks and other Eastern Orthodox churches (which were later worked into acceptable compromises in the long working sessions of the Council of Florence, 1438 to 1445); and a decree advising greater vigilance against heresy, the easiest target of all.

Proposals for genuine institutional reform within the Catholic Church hung fire ominously. French proposals for more local control ("Gallican" proposals, generally speaking) produced resistance from the loyalists of the Papal Curia. Nothing was accomplished at Siena in that area.

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