William "Billy" Walker (1860 - September 20, 1933) was an African American jockey. Born a slave in near Versailles, Kentucky, Billy Walker was the leading rider at Churchill Downs in the fall racing season of 1875-76 and the spring campaigns of 1876 through 1878. He was the winning rider aboard Ten Broeck in a famous July 4, 1878 match race at Louisville, Kentucky against the great California filly, Mollie McCarty. Wikipedia
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