John Jordan "Buck" O'Neil Jr. (November 13, 1911 – October 6, 2006) was an American first baseman and manager in the Negro American League, mostly with the Kansas City Monarchs. After his playing days, he worked as a scout and became the first African American coach in Major League Baseball. In his later years he became a popular and renowned speaker and interview subject, helping to renew widespread interest in the Negro leagues, and played a major role in establishing the Negro Leagues Baseball Museum in Kansas City, Missouri. He was inducted into the Baseball Hall of Fame in 2022 as an executive.
O'Neil was prominently featured in Ken Burns's 1994 documentary series Baseball. His life was documented in Joe Posnanski's 2007 book The Soul of Baseball.