One of my favorite underrated movies (which some might argue is terrible) is The 13th Warrior, where Antonio Banderas (Spanish) plays a Moor who falls in with a group of Vikings, several of whom are played by Irish and Germans.
In that vein, one of my favorite computer games of all time is Conquests of Camelot, where you play as Arthur and travel through various parts of Britain, then Gaza, then Jerusalem.
I feel like if it is done right, cross cultural stuff set in dark age or Christian/Medieval Europe can work just fine. Of course, if the character starts talking about racism and what not, then we have a problem.