Born in Charlestown, Massachusetts, Selfridge graduated from the United States Naval Academy in 1854.

At the beginning of the American Civil War, he helped with efforts to destroy the untenable Norfolk Navy Yard; and he then escaped from that burning and beleaguered base in the USS Cumberland, helping to save the sloop of war for the Union Navy.

He participated in the capture of the Hatteras forts and was on board Cumberland on 8 March 1862 when she was sunk by Confederate ironclad, CSS Virginia.

Although the route he proposed was not actually used for the Panama Canal, his work did show that Darien was not a good choice, thus narrowing down the construction possiblities.

[2] In 1885, Captain Selfridge, of the U. S. man-of-war Omaha, delegated a lieutenant to present his compliments to Captain De Saune, the French commander of the Isère, laden with the Statue of Liberty, and suggest that Gravesend Bay would be a safer anchorage than the Sandy Hook Horseshoe.