Captain Alexander Thompson (1759-1809) was born in New York City to James Thompson and Margaret Ramsay. Alexander married Abigail Amelia DeHart in 1784, and they had six children. Thompson fought in the American Revolution, first in a militia company commanded by Silvanus Seely (1777), and later as a lieutenant in John Lamb's artillery (1779-1783). In 1786, Thompson became a captain in the New York Militia Regiment of Artillery, and in 1794, President George Washington commissioned him to the Corps of Artillerists and Engineers stationed at Governor's Island (1795). His next posts were at Fort Niagara (1798) in New York, and Fort Lernoult in Michigan Territory (1800). He returned to New York City in 1802, and in 1806 became the military storekeeper at West Point, where he aided in the construction of the military academy there. He died at West Point on September 28, 1809.
Colonel Alexander Ramsay Thompson (1793-1837) was born in New York and was the youngest son of Captain Alexander Thompson and Abigail DeHart. He graduated from the United States Military Academy at West Point in 1812, and was commissioned 1st lieutenant in the 6th Infantry. During the War of 1812, Thompson fought in Canada under General James Wilkinson, and participated in the Battle of Plattsburg. After the war, Thompson served as captain at Fort Niagara, and in 1816 he married Mary Waldron Nexsen (1790-1858). They had one son who died in infancy. Over the next 20 years, Thompson rose to the rank of colonel and served at forts in New York, Michigan, Kansas, Louisiana, and Florida. He was killed in the Battle of Okeechobee during the Seminole War in 1837.
Reverend Alexander Ramsey Thompson (1822-1895) was born to Janette Nexsen and William Robert Thompson, brother of Colonel Alexander R. Thompson. He graduated from New York University in 1842 and soon after entered the seminary at Princeton. In 1846, he was ordained a Presbyterian minister, and later that year married Mary Carpenter. They had eight children. For the next 15 years, Thompson preached at various churches in New York and New Jersey before settling in Bridgeport, Connecticut. During the Civil War, Thompson served as chaplain of the 17th Regiment of Connecticut Volunteers. In 1862 he moved his family to New York City and took up a ministry at the 21st Street Dutch Reformed Church. There, he devoted much of his energies to supporting the New England Soldiers' Relief Association. At the end of the war, Thompson was awarded a Doctorate of Divinity from New York University, and in 1871 became the chaplain of the Roosevelt Hospital in New York City. Thompson died in 1895.