Who was expected to protect the pope?

The duties of protecting public order and security in the Vatican lay with the Papal Gendarmerie Corps, while the Swiss Guard, the Palatine Guard and the Noble Guard served mostly ceremonial functions.

The Swiss Guard of the Vatican is the only Swiss Guard that is still active today. The unit was founded by Pope Julius II in 1506. Many guards died protecting a later pope during the looting of Rome of 1527 (commemorating the anniversary of this 'martyrdom' has since become a tradition)