Francis I invited Leonardo da Vinci to France in his final years. In 1516, the French king arranged for Leonardo to leave Italy and enter royal service, offering him a residence and support near the Château d'Amboise.
Leonardo was then about 64 and no longer producing major paintings at his earlier pace, but Francis valued him as an artist, engineer, architect, and intellectual. Leonardo moved to France with several works, probably including the Mona Lisa, and lived at Clos Lucé, a manor connected to the king's residence by an underground passage.
A common mix-up is confusing Francis I with Louis XII, who also employed Leonardo in Milan. Francis I, however, was the monarch who brought him to France, where Leonardo spent the last years of his life and died in 1519.