1864-1922. After sailing to the West Coast as a merchant seaman in 1882, he settled in Portland, Oregon. There he was an instructor of drawing at the Bishop Scott Academy (now called Hill Academy) and was a founder of the Portland Art Association. About 1892 he moved to San Francisco where he remained. He worked there as a stevedore on the waterfront and later established a home and studio in the Sunset District at 1224 46th Avenue within walking distance of the ocean.

Hagerup painted nearly 6,000 oils of sand dunes, ships and marine scenes. One of his more important works is the 16' x 18' mural in the Assembly Room of the San Francisco Merchants' Exchange Building.

Due to alcoholism some of his paintings are uneven in quality; however, in his more lucid moments, he was a master of atmospheric seascapes. He died of a heart attack in his studio on March 13, 1922.