Fifth Council of the Lateran

The Fifth Council of the Lateran (1512–1517) is the Eighteenth Ecumenical Council to be recognized by the Roman Catholic Church and the last one before the Protestant Reformation.

When elected pope in 1503, Pope Julius II promised under oath to convoke a general council; however, as time passed, his promise was not fulfilled.

The Republic of Venice had encroached papal rights in Venetian territories by filling vacant episcopal sees independent of the pope, subjected clergy to secular tribunals, and disregarded the ecclesiastical jurisdiction of Julius II in other ways. In 1509, Julius II joined the League of Cambrai, a coalition to restore recent continental conquests by Venice to their original owners. Then, also in 1509, Julius II censured Venice with an interdict and deployed Papal States' armies into Venetian occupied Romagna. Venice suffered a complete defeat at the Battle of Agnadello on 14 May 1509, against the combined forces of the League of Cambrai. In 1510, Venice negotiated with Julius II, who withdrew from the League of Cambrai and removed the censure, after Venice agreed to, among other terms: to return disputed towns in Romagna; to renounce their claims to fill vacant benefices; to acknowledge jurisdiction of ecclesiastical tribunals over clergy and immunities of the clergy, including exemption from taxes; to revoke all unauthorized treaties made with towns in the Papal States; to abandon appeal to a future general council against the papal bans; and to concede free navigation of the Adriatic Sea to Papal States subjects.

The first stages of conflict between the Papal States and France began in 1510. King Louis XII of France demanded that the Republic of Florence should definitely declare its allegiance. Declaring allegiance to France would expose Florence to an immediate attack and alienate citizens who dreaded a conflict with the head of the Church. Florence was full of antagonistic parties and irreconcilable interests; in order to gain time, it sent Niccolò Machiavelli on a diplomatic mission to France in July 1510, where he found Louis XII eager for war and inclined towards the idea of a general council to depose Julius II.