What year was Donkey Kong created?
The character NOT the game
1981. Nintendo had recently failed to purchase the popular "Popeye" comic strip, so instead they created new characters for future games. He first appeared in an arcade game titled "Donkey Kong" in 1981.
Wikipedia: Donkey Kong was Mario's first opponent in Nintendo's popular 1981 arcade game, Donkey Kong. Apparently the game was his first appearance.
He was always there... On the first day he created the heavens and the earth.