939 - 1946 3c US Armed Forces: Merchant Marine
US #939 was issued to honor the Merchant Marine’s role in WWII.

On March 15, 1938, the Merchant Marine Cadet Corps was established. Merchant Marines transport cargo and passengers in peacetime and are called upon in times of war to deliver troops and supplies wherever needed.

America’s Merchant Marines traces its roots to the colonial era and first entered combat during the Revolutionary War. On June 12, 1775, a group of citizens who had learned about the fighting at Lexington and Concord captured the British schooner HMS Margaretta. Earlier in the month, the British and a Loyalist merchant had given the residents of Machias, Maine, an ultimatum – either load their ships with lumber to build British barracks in Boston or starve (the merchant had much-needed supplies on his ships). The citizens initially voted against trading, but then the British brought the Margaretta within firing distance of the town. A new vote was held, and the residents agreed to trade, but when the merchant refused to sell to anyone who had voted against trade, the local militia made plans to seize the merchant and the commander of the Margaretta, James Moore. Moore escaped, but in the process had to maneuver  the Margaretta against hard winds and the main boom and gaff broke. With the ship crippled, the Americans were able to catch up the next day in two sloops, the Unity and Falmouth Packet. They overwhelmed the crew of the Margaretta, mortally wounding Moore, and the second-in-command surrendered.

345963 - First Day Cover
US #939 – Classic First Day Cover

Once word of this revolt reached Boston, the Continental Congress issued Letters of Marque to privateers, authorizing them to attack and capture British vessels. The privateers soon began interrupting British shipping along the East Coast and across the Atlantic. Their actions predated both the US Navy and Coast Guard, which were founded in 1775 and 1790, respectively.

US merchant ships would go on to participate in every American conflict that followed. In fact, they were one of the contributing factors to the War of 1812. At the time, the British Navy didn’t recognize naturalized American citizenship and would stop American merchant ships and forcibly place anyone born a British citizen (which included many Americans) into military service. This practice was one of several reasons the nations went to war in 1812. That war was largely fought by American merchant ships. The US Navy and privateers captured a combined 30,000 prisoners.

4548-51 - 2011 First-Class Forever Stamp - U.S. Merchant Marine
US #4548-51 pictures different types of Merchant Marine ships through the years.

The Mexican-American War was the first in which the US Army invaded an enemy’s land by the sea. During that conflict, merchants provided dozens of ships to the US to support the cause.

During the Civil War, control of the nation’s waterways was important to both sides. The Union blockaded southern seaports and used hundreds of merchant vessels. The Confederates issued Letters of Marquee, attempting to capture Union privateers, but were largely unsuccessful.

335532 - First Day Cover
US #4548-51 – Plate Block First Day Cover

By the time of the Spanish-American War, the Merchant Marine was greatly reduced and unable to supply the large number of ships to the conflict that it had in the past. However, merchants did provide the small number of ships they could for that war.

By World War I, the Merchant Marine had rebounded and would supply a significant number of ships to the war effort. These ships carried supplies across the Atlantic to the American Expeditionary Force. One naval commander commended them saying, “The skill and seamanship of these sailors was something that amazed naval officers, and they proved themselves to be seamen in a sense that naval officers never have the opportunity to become. Without the merchantmen’s skill, courage, and loyalty, the war could not have been won.”

Then on June 29, 1936, President Franklin Roosevelt signed the Merchant Marine Act of 1936. The act was passed to “further the development and maintenance of an adequate and well-balanced American Merchant Marine, to promote the commerce of the United States, to aid in the national defense, to repeal certain former legislation, and for other purposes.” This act also created the US Maritime Commission, which realized that a trained merchant marine force would be essential to US interests.

2094 - 1984 20c Literary Arts: Herman Melville
US #2094 – Melville wrote several stories inspired by his time as a Merchant Marine.

This led to the creation of the US Merchant Marine Cadet Corps two years later on March 15, 1938. Up until this time, training programs were largely run by the states. This new program used civilian Maritime Commission and US Coast Guard instructors to train Merchant Marines.  They trained on ships and in temporary locations until the US Merchant Marine Academy was completed in 1943.

The Merchant Marines would grow quickly leading up to and during World War II – nearly quadrupling in size from 55,000 to 215,000. It provided one of the largest merchant fleets of the war and has been credited as one of the most significant contributions of any nation during the conflict. Unfortunately, they also had the highest casualty rate of any service, with 1 in 26 losing their lives.

The Merchant Marines went on to participate in the Korean, Vietnam, and Gulf Wars as well, providing hundreds of ships and thousands of men to each conflict. In Vietnam, the Merchant Marines carried 95% of the supplies used by American forces. And during the first Gulf War, they delivered 12 million tons of vehicles, helicopters, ammunition, fuel, and other supplies.

Today, the Merchant Marines consists of over 400 ships and 69,000 officers and sailors.

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  1. They are not Merchant Marines. The Merchant Marine is an industry. People who work in that industry are Merchant Mariners.

  2. My father spent 47 years in the Merchant Marine. What a fascinating and challenging life he had! Some of the drama took place onboard the ship; once they were attacked by pirates. And there was even a murder. Did you know that there are jail cells on ships? He had been to nearly every port in the world. He would often bring my sister and I stamps to add to our collection.
    Thank you for this wonderful article; there was a lot of new information!

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