They were primarily used for hunting and so the breed dwindled in numbers as populations of wolves and elk in Ireland dramatically decreased at one point.
By the 18th century, the breed was hard to come by. Luckily, Capt. George A. Graham made it his mission to ensure there were still a few Irish Wolfhounds left in Ireland. He found the remaining dogs and bred them.
Around the same time, Major H.D. Richardson began breeding Irish Wolfhounds to help save the breed.