North Brendania was first discovered by Saint Brendan of Ireland in 754, and became a hub of colonization along with South Brendania. The Irish was first to colonize it, and later the Norse, Welsh, Norman, French, Chinese, English, Spanish, and others.
Saint Brendan was searching for Paradise when he came upon North Brendania, landing near OTL Connecticut. Saint Brendan had already landed in Greenland, but the first landing in the mainland is generally thought of as the actual point of discovery. The first settlement there was New Clonfert, founded by Saint Brendan. The relationship between the settlers and the Native Brendanians were peaceful for the most part, though small skirmishes began later. Saint Brendan, also known as Saint Brendan the Discoverer, explored more of North Brendania. In 760 he discovered Cape Cod, naming it after the abundance of cod fish there. Another settlement was started there, known as Codtown.
As time went on another nation made it to North Brendania, the Norse. In 830 it started the colony of Vinland. The Norse began explorations into the inland. Unlike the Celtics, the Norse waged war against the Natives in attempts to gain their supplies. Naddoddr the Explorer, a Norse explorer, explored much of the coast of Markland.