Born in 1823 to Irish parents, Flavel relocated to the West coast of the United States in 1849, working as a tugboat operator between Sacramento and San Francisco, California.

Flavel would go on to amass a fortune with a business managing pilot boats on the Columbia River, making him a prominent local figure, and one of the first millionaires in Oregon.

His family estate, known as the Captain George Flavel House, was donated to the Clatsop County Historical Society by his great-granddaughter after her inheritance of it in 1933, and contemporarily functions as a museum.

[3] He sailed around Cape Horn and also spent time in California during the state's Gold Rush era[4] before relocating to Astoria, Oregon, then a settlement based around John Jacob Astor's American Fur Company.

[8] One of the only mariners in the state to possess a captain's license, Flavel and his partners were able to establish a virtual monopoly on bar piloting and ship tours on the Columbia, which amassed him a great deal of wealth.

[4] In January 1852, during a particularly strong gale, the SS General Warren lost its fore-topmast and began to leak near Astoria; Flavel was unable to rescue the ship, and forty-two people aboard died with its sinking.

With the continued success of his business enterprise, the family divided their time between Oregon and San Francisco, California,[4] and Flavel was able to afford his children extensive educations in Europe; his daughter, Nellie, became a classically-trained pianist, and performed with the Organists' Guild of Portland.