The Pope is guarded by 135 Swiss troops known as the Pontifical Swiss Gaurd. They were initially engaged in 1506 by Pope Julius II, who required personal security from Church adversaries. They are immediately identified by their brightly coloured striped jerseys. Anyone can join the Swiss guard, but they must be male, between the ages of 19 and 30, and 5' 8" tall. In addition, one must be a Christian and have undergone basic military training.