In Greek myth the Dioscuri (or the Gemini stars) were mortal sons of Leda, one born of Zeus and one of Tyndareus, who at death were made into gods:
Polydeukes and Kastor were gods of horsemanship.
The Dioscuri (Kastor and Polydeukes) were horsemen and thus gods of horsemen in Greek myth.
In Supernatural, God didn't create Death. Death told Dean that he was much older than God and that he would reap him eventually. The reason Death was one of the horsemen Dean and Sam had to kill was that Lucifer summoned and bound him with a spell.
The collective nouns are a cavalcade of horsemen and a troop of horsemen.
Iron Horsemen was created in 196#.
Kentucky Horsemen ended in 2009.
Kentucky Horsemen was created in 2003.
Horsemen of the Esophagus was created in 2006.
The Horsemen Project was created in 2000.
Brooklyn Horsemen was created in 1926.
Brooklyn Horsemen ended in 1926.
Horsemen of the Esophagus has 303 pages.
A Tribute to the Four Horsemen was created in 2002.