A Franco-Polish Alliance was formed in 1524 between the king of France Francis I and the king of Poland Sigismund I.[1]
Francis I was looking for allies in Central Europe to create a balance against the power of Habsburg Emperor Charles V.[1] Queen Bona Sforza, the Italian wife of Sigismund, was instrumental in promoting the alliance, with the objective of recovering sovereignty of Milan.[2] Sigismund himself was motivated by such an alliance because Charles V was getting closer to Russia, thus threatening Poland on two fronts.[2]
The negotiations were handled by Antonio Rincon in 1524, who was then followed by Jerome Laski.[1] Through the agreement, the son of Francis, Henry, Duke of Orléans, was to marry a daughter of Sigismund I, and Sigismund's eldest son was to marry a daughter of Francis I.[1] According to the same agreement, Sigismund was supposed to support Francis' efforts at reconquering Milan to which Sigismund had some right through his earlier marriage with Bona Sforza.[1] The alliance was effectively signed in 1524.[2]
The agreement fell through, however, when Francis I was vanquished by Charles V at the Battle of Pavia in 1525.[1] When Francis again looked for Central European allies after 1526, he would look at Hungary instead and finally formed a Franco-Hungarian alliance with King Zapolya in 1528.[1]