Who is the best jockey of all time?

There’s no clear answer to that question because there have been many great jockeys in different eras.
In the late 1800s, the African-American jockey Isaac Murphy was dominant, winning with about a third of his mounts, including three Kentucky Derbies.
Earl Sande was dandy in the 1920s-30s, wining the second Triple Crown in 1930 on Gallant Fox and getting himself immortalized in Damon Runyon’s poems.
In the 1940s and early ‘50s, Eddie Arcaro was dominant, capturing the Kentucky Derby five times and becoming the first rider ever to win two Triple Crowns aboard Whirlaway and Citation.
Enter Bill Shoemaker, who won almost every major race during a career that saw him riding at the highest levels of the sport over four decades before retiring in 1989.
There have been many great riders since then, but the increasing level of competition has prevented anyone from dominating to the same extent as the reinsmen of yore.