The area of North Richmond was populated by Ohlone tribes which settled the area in the 6th century. However, Hokan speaking people may have inhabited the area even earlier, and archaeological evidence shows human settlement to have begun at least by 4000 BC. The Ohlone tribesmen subsisted from hunter-gatherering the bountiful amount of land and sea life of the area. Especially the great amounts of seafood made available along the coastline of Castro Cove and the surrounding marshlands and delta of Wildcat and San Pablo creeks. The majority of present-day North Richmond was territory of the Karkin tribe (or "Carquinez") however the land lies on what was a border area with the Chocheño tribe and likely had influences of both groups. The tribes made great use of the salmon and trout runs on the rivers. However, today, culverting and damming has decimated the habitat for these species and they are rarely present ever at the opening of the watercourse.