In 1512, as papal legate for Italy and Germany, he was; appointed commander of a Swiss and Venetian army, drove the French from Milan and established Maximilian Sforza as duke.
However, as Louis XII again captured Milan after the death of Julius II, Schiner once more took the field at the head of the Swiss Confederates, and defeated the French in the battle of Novara (1513).
When under Francis I of France the French recrossed the Alps, Schiner led the Swiss troops, part of which had retired, at the unfortunate battle of Marignano (1515).
During his long absence from home the French party there, under his bitter enemy George Supersax, raised a rebellion and drove him from Sion.
But for his passionate hatred of France, he would have been elected the successor of Leo X; however, Pope Adrian VI called him to Rome as administrator of the States of the Church.