Switzerland may be wealthy now, but 500 years ago it was a poor country whose young men often resorted to seeking work abroad as mercenaries.
Swiss mercenaries were in high demand in Renaissance Europe, but the pontifical Swiss Guard is the last remaining legacy of the tradition.
The tiny force is responsible for the Pope’s safety, including the security of the Apostolic Palace, and acts as the de facto armed forces of Vatican City, the world’s tiniest sovereign state.
The 130 members of the Swiss Guard are required to be Catholic, unmarried Swiss citizens who have completed Swiss military service.
They need to be at least 5ft 8in tall and between the ages of 19 and 30.
The commandant of the Swiss Guard raised the prospect in 2009 that the corps might one day admit female recruits, but said it remained a long way off.
Guards are expected to be ready to lay down their lives in defence of the Pope and are supposed to be of impeccable moral and religious character.
They can be seen on guard outside the Vatican every day, dressed in striped blue, red and gold uniforms and carrying halberds as their traditional weapons.
They are also equipped with modern firearms – the same handguns and machine guns which are used by the Swiss army.
The idea that the uniform was designed by Michelangelo is a myth – it is simply a legacy of military uniforms that were common in Europe during the Renaissance.
The Swiss Guard’s most significant military engagement was in 1527 when 190 guards died fighting Holy Roman Empire troops during the Sack of Rome, allowing Clement VII to flee to safety from the Vatican through a stone passageway.
The Swiss Guard’s role as the Pope’s armed force is complemented by the Vatican’s Corps of Gendarmes, which was established in 1816 by Pope Pius VII and whose recruits are Italian.