<<<< On the second day of school, the French boy came up and punched him on the playground for no reason.>>>
...and did your boy punch him back, which was probably what was needed to start a relationship of mutual respect? Tom Browns Schooldays, Biggles, and all that - ie, stand up to a bully with a bigger stick than the one he hit YOU with.
Fashions in parenting and teaching may have changed, but human nature hasn't.
I teach in a French school with a sprinkling of english kids, none of what you describe happens TTBOMK.