Muhammad Ali, the reigning world heavyweight boxing champion, entered the combative ring of politics and culture by refusing to
serve in the United States military at the height of the Vietnam
War on this day in 1967.

"I ain’t got no quarrel with those Vietcong," Ali famously said the
year before, the exact quote the source of some dispute, in a
battle that made it all the way to the United States Supreme Court. 

He later wrote, "I refuse to be inducted into the Armed Forces
of the United States because I claim to be exempt as a minister
of the religion of Islam."