"Blaine is a city at the northwest boundary and an important United States Customs port, on Drayton Harbor, Semiahmoo Bay. It was named by Cain Bros., townsite proprietors, who filed their first plat September 13, 1884. In 1858 it was an ambitious settlement called Semiahmoo, the name of the tribe of Salish Indians who then inhabited the Semiahmoo Bay Country."
-Lottie Roeder Roth, "Origin of names," History of Whatcom County. Chicago: Lewis, 1926. Chapter XLI p. 937-961.
Blaine was settled in 1856 when the U.S. Boundary Survey Commission surveyed the 49th parallel and in 1858 when the cry of gold echoed along the Fraser River, B.C. Two towns both sharing the name Semiahmoo (Central Blaine and Semiahmoo spit) prospered by the commissions activities and from outfitting the miners going north.