The early beginnings of rodeo trace all the way back to the Spanish ranches of 1700. Rodeo events are derived from ranch chores in informal contests. It is also is claimed that the first rodeo was in 1884 in Deer Trail, Colorado when two neighboring ranchers competed to settle an argument about who was better at performing ranch tasks.

It's old, and rooted from farm chores. The first anti-rodeo groups started in 1924 according to what I could find.