As a symbol of mourning for the death of Pope Leo X (1 December 1521), Giovanni added black stripes to his insignia, whence comes his nickname, Giovanni delle Bande Nere (or Giovanni of the Black Bands). In August 1523 he was hired by the Imperial army, and in January 1524 he defeated the French and the Swiss at Caprino Bergamasco. In the same year another Medici, Giulio di Giuliano, became Pope, and took the name of Clement VII. The new Pope paid all of Giovanni's debt, but in exchange ordered him to switch to the French side of the ongoing conflict. He did not take part in the battle of Pavia, but was soon severely wounded in a skirmish and later had to move to Venice to recuperate from his wounds.