@kaia
Translation: "I considered men of different faiths as enemies, and I killed many of them. Here I mourned their destiny as well as ours. Let my sword remain here to guard this mountain. Let no one take it away. Not unto us, O Lord, not unto us, but to thy name give the glory".

The last paragraph is latin, everything else is probably some form of Tuscan vernacular (think of an ancient Italian language that borrows some terms from Latin). The sculpture supposedly references a local legend about five templars seeking protection in Italy after the King of France tried to kill them for their gold (except the Pope sided with the King and the templars were forced to disappear from public life). Thing is, the "legend" was probably fabricated as well, quite recently too.
Pretty sure the sword got stolen at some point.