The Irish Setter, like many dog breeds, has a history filled with complex twists and turns that have shaped the dog we love today. Irish Setters descend from the same rootstock that gave rise to all the setter breeds, but there is good reason to believe they may be the oldest of them all. The spaniels that became setting dogs were in Ireland since at least the 16th century. During this time, the landscape of the island was quite different from what it is today.