Facing the threat of Italian nationalism, an international force of light infantry was formed to protect the Papal States. They were known as the Papal Zouaves. Zouaves refers to the Franco-North African Infantry regiments that wore funny looking uniforms inspired by a tribe of Berbers called Zouaoua. Well, they were relatively funny looking compared to the other troops at the time, with their baggy pants and fezzes. Zouaves were used on both sides of the U.S. Civil War, so you can easily contrast their uniforms with the conventional troops' attire, I digress.
They were a French based force, but were made up of Catholics from all over the world. It's pretty cool that Catholics men from different countries and cultures came together in the service of the the Holy Father. I'm kind of bummed that they don't exist anymore. I would have seriously considered joining this group had they still existed, since the Vatican Guard was not an option for me. They have this thing about being Swiss and taller than 5' 8".
Post on the Pontificio Rifle used by the Papal Zouaves here.