The breed originated in Newfoundland from dogs indigenous to the island, and the big black bear dogs introduced by the Vikings in 1001 A.D. With the advent of European fisherman, a variety of new breeds helped to shape and re-invigorate the breed, but the essential characteristics of the Newfoundland dog remained. By the time of colonization was permitted in 1610, the distinct physical characteristics and mental attributes had been established in the breed for all time. In the early 1880s fishermen from Ireland and England traveled to the Grand Banks of Newfoundland where there were two types of working dog: one more heavily built, large with a longish coat, whereas the other was lighter in build, an active, smooth-coated water dog. The heavier one was the Newfoundland and the other was the Labrador Retriever or the St. Johns breed of Newfoundland. The dogs were used in similar ways to pull fishnets and heavy equipment.

During the Discovery Channel's second day of coverage of the AKC Eukanuba National Championship on December, 03, 2006, anchor Bob Goen reported that Newfoundlands exhibit a very strong propensity to rescue people from water. Goen stated that 1 Newfoundland alone once aided the rescue of 63 shipwrecked sailors.