The 28-year-old said Friday that he would not stand for the national anthem before games or at any other time.

"I'm not going to stand up to show pride in a flag for a country that oppresses black people and people of color," he said. "To me, this is bigger than football and it would be selfish on my part to look the other way. There are bodies in the street and people getting paid leave and getting away with murder."

Kaepernick received a hailstorm of criticism, but he is one of many celebrities that have used their platform to take a stand.

In his 1972 autobiography, "I Never Had It Made," Jackie Robinson detailed the moment he realized he could not "stand and sing the anthem" or "salute the flag." 

"There I was, the black grandson of a slave, the son of a black sharecropper, part of a historic occasion, a symbolic hero to my people. The air was sparkling. The sunlight was warm. The band struck up the national anthem. The flag billowed in the wind. It should have been a glorious moment for me as the stirring words of the national anthem poured from the stands. Perhaps, it was, but then again, perhaps, the anthem could be called the theme song for a drama called The Noble Experiment. Today, as I look back on that opening game of my first world series, I must tell you that it was Mr. Rickey's drama and that I was only a principal actor. As I write this twenty years later, I cannot stand and sing the anthem. I cannot salute the flag; I know that I am a black man in a white world. In 1972, in 1947, at my birth in 1919, I know that I never had it made."

More recently, Mahmoud Abdul-Rauf played point guard for the Denver Nuggets from 1990 to 1996, when he made headlines for his refusal to stand for the anthem. 

In 2003, college basketball player Toni Smith made national headlines when she protested the Iraq War by turning her back on the flag during the national anthem.

"It's a very terrible thing that happened on Sept. 11," Delgado told the Toronto Star at the time. "It's (also) a terrible thing that happened in Afghanistan and Iraq. I just feel so sad for the families that lost relatives and loved ones in the war."

Delgado ended the protest in 2006 when he was traded to the New York Mets.

>> Looks like Colin Kaepernick is sitting through the national anthem for some time

So far, despite the backlash, Kaepernick has said Sunday that he's sticking with his stance.

"I'll continue to sit," he said Sunday. "I'm going to continue to stand with the people that are being oppressed. To me, this is something that has to change, and when there's significant change -- and I feel like that flag represents what it's supposed to represent, and this country is representing people the way it’s supposed to -- I'll stand."

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