Elephants were used successfully in India and SE Asia up until the end of the 19th century. They even mounted cannon on them and used them as mobile artillery.
Note: Hannibal used African Elephants—somehow they learned to domesticate them. The modern world has forgotten this. If the African Elephants could be domesticated like the Indian/Asian they might be used to help Africa and not seen as tings to kill for ivory. Elephants are good against cavalry. Horses hate them and will not ride against them. Elephants were the Tiger Tanks of the Ancient World and gave the Romans fits for a while.