Which famous world war ii unit, made up entirely of japanese-americans, bears the distinction of being the most highly decorated military unit in american history?

The correct answer is the 442nd Infantry Regiment

They were a unit of Japanese American soldiers who served in Europe, mostly France and Italy and became the most highly decorated unit in American history. Out of the 14 000 soldiers who served in the unit, 9000 of them got the purple heart, they got eight Presidential Unit Citations, and 21 congressional medal of honor.