- Card series: Pilgrims
- League: National League
- Hall: National Baseball Hall of Fame
William Joseph Klem (nee Klimm) (1874-1951) was the great founding-father of baseball umpiring. He brought a level of expertise and dignity that helped transform officiating and the game itself. And he was colorful: “It ain’t nothin’ till I call it;” “Gentlemen, he was out because I said he was out;” and “Son, when you pitch a strike, Mr. Hornsby will let you know.”
- Joined the NL crew in 1905, worked a record 18 World Series (no one else did more than 10)
- Was the longest-tenured and oldest umpire until exceeded in both by Bruce Froemming
- Elected to Hall of Fame: 1953