A native of New York City, Moran was 18 when, in 1875, he arrived penniless in Seattle, a frontier outpost in the Pacific Northwest, which had been settled in November 1851, and only incorporated between 1865 and 1869.
The Moran Brothers Company prospered during the Klondike Gold Rush when, among other projects, they built a fleet of twelve 176-foot (54 m) paddlewheel riverboats (hull Nos.
[4] Among his administration's rebuilding efforts was the public overhaul of Seattle's water system and the establishment of a savings and loan association, which later became Washington Mutual.
[5][6] Following his mayoral service, Moran devoted all his efforts to his shipbuilding business and, in 1904, climaxed his career with his shipyard's launch of the USS Nebraska, Washington state's only battleship.
He was told in 1905 that he had one year to live, and retreated to Orcas Island in Puget Sound's San Juans, where he built the Moran Mansion—surrounded at that time by 7,800 acres (32 km2) of land—that is now the centerpiece of Rosario Resort.