John Mason Loomis (January 5, 1825 – August 2, 1900) was a nineteenth-century American businessman and lumber tycoon from Chicago who was known for developing the city of Ludington, Michigan.

Loomis served as a colonel in the Illinois militia, mobilized as part of the Union Army during the American Civil War, held several commands, and fought in several major battles.

[1] Loomis attended public school in Connecticut and received initial business training working at his father's store as a teenager.

[9][11][12] Other local entrepreneurs copied Loomis's techniques, establishing the salt industry in northwestern Michigan.

[9] The village of Pere Marquette benefited from these local lumber and salt industries and developed into the city of Ludington.

He was then appointed as a midshipman in the United States Navy, but opportunities for active service and travel were rare so he resigned.

He then joined the United States Merchant Marine, traveling to China and other Asian countries, returning to Chicago in 1845.

[13] When the American Civil War began in 1861, Loomis was a first lieutenant in the Chicago Light Guard[a] with a reputation as a devoted and skilled military leader.

[18] After the war, Colonel Loomis became a Companion of the Illinois Commandery of the Military Order of the Loyal Legion of the United States.

[27][28][29] Loomis was on the board of directors of the Chicago Relief and Aid Society, a charity for those left homeless and destitute after the fire of 1871.

In 1879, Loomis founded the Illinois Commandery of MOLLUS, the Military Order of the Loyal Legion of the United States, and became its commander in 1884, succeeding Philip Sheridan.

Although not considered a politician by historians Hyland MacGrath and George Irving Reed, Loomis was active in the selection of candidates to governmental offices.

[30] He built a home at 55 Lake Shore Drive, in Chicago,[33] dying in that city on August 2, 1900,[17] and is interred at Rosehill Cemetery.