Pope Francis -- Cruisin' D.C. ... In A Fiat!

Pope Francis just arrived in the not-so-holy land of Washington, D.C. and he's keeping it European and austere ... chauffeured in an Italian-made Fiat.

Francis touched down Tuesday afternoon at Andrews Air Force Base in Maryland before heading to the Vatican Embassy. Sticking true to his nickname of "The People's Pope" .. the Fiat 500 starts right around $20k.

Fiat motors tweeted "#blessed."

Kind of blows the Jennifer Lopez Fiat commercial away, right?