This street was created in 1907 as part of the plat of Magnolia Park, filed by the Magnolia Park Company. Insurance man Ferdinand Bosher Edgerly (1881–1966), president of the company, lived most of his life in Manchester, New Hampshire, but according to his obituary moved to Seattle after graduating from Dartmouth College in 1904, returning to Manchester in 1913. It would appear he named Dartmouth Avenue after his alma mater.
Dartmouth Avenue W begins at the end of W Howe Street, just east of Magnolia Way W, and goes just under 300 feet southwest to rejoin Magnolia Way W. Almost all of it, however, functions as private driveways for a number of houses with Magnolia Way addresses; the initial paved portion is less than 75 feet long and serves the only house with a Dartmouth Avenue address.
Born and raised in Seattle, Benjamin Donguk Lukoff had his interest in local history kindled at the age of six, when his father bought him settler granddaughter Sophie Frye Bass’s Pig-Tail Days in Old Seattle at the gift shop of the Museum of History and Industry. He studied English, Russian, and linguistics at the University of Washington, and went on to earn his master’s in English linguistics from University College London. His book of rephotography, Seattle Then and Now, was published in 2010. An updated version came out in 2015.