Francis Marion was born in February 1732, the 5th and youngest son of Gabriel Marion Sr. and his wife Esther Cordes. He was the grandson of French Calvinist Protestants, known as Huguenots, who fled their homeland in the late 1600s due to anti-Protestant religious persecution under French King Louis XIV. His parents were maternal first cousins as his 2 grandmothers were sisters: Judith and Esther Baluet. His father's family was from the Poitou-Charentes region of western France while his mother's family were from Mazamet, in the Languedoc region of south-western France. The family spoke French and English and were educated, demonstrating their upper-middle-class background. 
Francis was puny child, probably premature - he was said to be "the size of a [red/cooked] lobster" at birth. His knees and ankles were slightly deformed but straightened later.
Initially, Francis Marion wanted to be a sailor and at 15 signed on with a schooner going to the West Indies from Charleston. On their way back, a whale rammed the schooner and sank it. Captain and crew escaped in a boat and drifted for six days. Two men died; the day after, they were rescued by another vessel. Francis returned to his family plantation, his "close call" ending his maritime vocation.
Francis Marion did not give up the idea of adventure, however, and began his military career in 1757, shortly before his 25th birthday. He and his brother Job Marion enrolled in the South Carolina militia under British command and campaigned against the Cherokee in the French and Indian War in the early 1760s.
From June 1775-1782, Francis Marion fought against the British in the American Revolutionary War, as an officer in the Continental Army and the South Carolina Militia. Despite several defeats, allowing the British and their local Tory allies to control most of South Carolina from 1777 to 1782, Colonel (later Brigadier General) Marion and his Continental "irregulars" adopted guerilla tactics, based on their intimate knowledge of South Carolina's lowlands, leading to his nickname of "Swamp Fox," given him by an outwitted British officer, Colonel Banastre Tarleton. He is considered a father of modern guerrilla and maneuver warfare, and is credited in the lineage of the United States Army Rangers and the other American military Special Forces such as the "Green Berets". 
Francis Marion was elected to the South Carolina State Assembly in January 1782 in Jacksonborough but he only temporarily left his troops; in June he put down a Tory Loyalist uprising on the Pee Dee River. His plantation was burned but after Great Britain withdrew from the Southern states he returned to Berkeley County to restore it. The 1783 Treaty of Paris ended the American Revolution.
On 20 April 1786, at 54 years old, Francis Marion married his cousin, 46-year-old Mary Esther Videau, b: ca. 1740 who had refused him once before. Given their ages, they had no children together. Marion named great-nephew Francis Marion Dwight his heir on the condition that young Dwight change his surname to Marion (which he did in 1793 by a special act of the South Carolina legislature). Unfortunately, Francis (Dwight) Marion had no sons to carry on his adopted family name. 
After the American Revolution, Francis Marion was elected to two terms in the State Senate of South Carolina in 1782 and 1784. He was also a delegate to the South Carolina Constitutional Convention and voted to join the Union. He was also named Commander of Fort Johnson on nearby James Island, which paid him $500 annual salary, enough to allow him to rebuild his Pond Bluff plantation.
Brigadier General Francis Marion passed away on 27 February 1795, the day after his 63rd birthday, at his Berkeley County, South Carolina, plantation. He was buried at the Belle Isle Plantation Cemetery, Saint Stephen's Parish, Berkeley County, South Carolina, USA.  His wife survived his passing. Mary Esther (Videau) Marion passed away on 26 July 1815 and was buried next to her husband at the Belle Isle Plantation Cemetery. 
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