The oldest son of a wealthy Belfast merchant, Thomas H. Marshall led a rather short and tragic life.
Born in Belfast in 1826 he was forced to leave Bowdoin College in his sophomore year for reasons of health.
Returning to Belfast he engaged in his father’s mercantile business and the gentlemanly pursuits of his day including a captaincy in the local Volunteer Militia Company, the Belfast City Greys, and a try at public office.
He was elected to represent Belfast in the Maine House in 1857 and 1858 and then served two years in the State Senate, being elected Senate President in 1860.
A quiet man, respected more for his gentlemanly qualities than his brilliance, he chose immediately to pursue a military career at the outbreak of the war in 1861.
Filling up the ranks of his unit, the City Greys, he took them into the Fourth Maine Regiment upon its formation.
When it came time for those men to elect their officers, he was chosen as their Major. At the battle of Bull Run the Fourth Maine made up a part of Howard’s Brigade consisting of the Third, Fourth, Fifth Maine and the Second Vermont.
This Brigade reached the field when the day was already lost and just in time to join the Union retreat. Although green and exhausted troops, they gave a good account of themselves and Major Marshall was commended for his coolness under fire.
Transferred to the newly formed Seventh Maine, first as its Lieutenant Colonel and later as its Commander, Marshall was taken ill with fever at their encampment in Baltimore and died together with eighty of his men. He was thirty-five at the time.