1910 Johnson–Jeffries riots

"When Johnson trounced Jeffries - and it was a bloody rout - the
defenders of white male supremacy were very publicly hoist by their own petards. They had insisted upon framing the fight as a contest to demonstrate which race could produce the superior specimen of virile manhood. Johnson's victory was so lopsided that the answer was unwelcome but unmistakable. After the fight, the black Chicago Defender exulted that Johnson was 'the first negro to be admitted the best man in the world.' The ensuing violence showed what a bitter pill that was for many white American men to swallow. Race riots broke out in every Southern state, as well as in Illinois, Missouri, New York, Ohio, Pennsylvania, Colorado, and the District of Columbia. Occasionally, black men attacked white men who were belittling Johnson. In most of the incidents, however, rampaging white men attacked black men who were celebrating Johnson's victory. In Manhattan, the New York Herald reported, 'One negro was rescued by the police from white men who had a rope around his neck.... In Eighth Avenue, between Thirty-Seventh and Thirty-Ninth Streets, more than three thousand whites gathered, and all the negroes that appeared were kicked and beaten, some of them into insensibility.... Three thousand white men took possession of Eighth Avenue and held against police as they attacked every negro that came into sight.' Contemporary reports put the overall national toll at eighteen people dead, hundreds more injured."

 - Gail Bederman, Manliness and Civilization