15. Irish Wolfhound
From cats to dogs, the Irish wolfhound claims its place as the largest breed of dog globally, with a history dating back to ancient times. Revered for its hunting prowess, this gentle giant played an essential role in both battles and peaceful times. Sadly, their numbers dwindled in the past, but the dedication of one man helped bring them back from the brink. Today, the Irish wolfhound remains a rare breed, facing the challenges of genetic diversity.