I've heard that there's a group that has been responsible for the personal safety of the Pope since 1506. Is this true?

the swiss guards

That's the Swiss Guard, founded by Pope Julius II from among the ranks of Swiss mercenaries at the start of the 16th century, though their service isn't unbroken. The biggest battle they fought came in 1527, when 147 guards including their commander, were killed fighting the forces of Charles V. Nowadays, they're responsible for the security of the Apostolic Palace, the entrances to the Vatican City and the safety of the Pope.

They currently number 100, and must be Roman Catholic males of Swiss nationality who have completed basic training with the Swiss military and can obtain certificates of good conduct. Recruits must be between 19 and 30 and at least 174 cm (5ft 9in) tall. The term of service is between two and 25 years. Their official dress uniform is a jumpsuit colored in blue, red, orange, and yellow, but their working uniform is more functional, consisting of blue coveralls with a black beret.

The Swiss Guards, whose 'colorful uniforms" were designed by MichelAngelo are literally from the Catholic cantons of Switzerland and are celebrating 500 years this year, founded by Pope Sixtus, whose name gives is the Sistine Chapel. They gave their lives to defend the Pope when the Popes were involved in regular battles as political-religious rulers. There are un-uniformed and differently- uniformed officers all around the Pope and in Vatican City today because of the danger of assassination, arson, vandalism, as happened when John Paul 11 was almost killed by an assassin's bullet in St. Peter's Square, and someone hacked at the Pieta in the Basilica, Pope Paul VI was attacked by a knife-wielding man in the Phillipines. The Bible says "the poor you will always have with you" the same goes for the "Nuts" some of whom write some "squirrely" stuff on these postings!

Swiss Gaurds. >.<