How did Pope Paul III try to make peace between Emperor Charles V and King Francis I of France?

Pope Paul III sought to mediate the long-standing conflicts between Emperor Charles V and King Francis I primarily to encourage them to unite their forces against the Ottoman Turks, who posed a significant threat to Italy and the broader interests of Christendom.1

To achieve this, the Pope employed a strategy of careful, tortuous diplomacy, intentionally avoiding taking sides with either monarch. A pivotal moment in these efforts occurred in 1538, when Pope Paul III traveled to Nice specifically to bring the two rulers together for peace negotiations. Throughout his pontificate, he consistently urged both leaders to cease their internal wars and redirect their military efforts toward defending against external threats.1