Francis Marion's military experience began in South Carolina's militia during campaigns against the Cherokee in the late 1750s and early 1760s. A planter and provincial politician, he joined the Revolutionary cause in 1775 and became an officer in the Second South Carolina Regiment. He served in the defense of Sullivan's Island in 1776 and commanded his regiment during the failed allied assault on Savannah in 1779.

An injury kept Marion away when Charleston surrendered to the British in May 1780. After the collapse of major American forces in the state, he organized militia resistance in the Pee Dee region. His partisans used intelligence, rapid movement, ambushes, and terrain to disrupt communications, attack isolated detachments, and release prisoners. Their strength varied, and operations depended on local support rather than a permanent conventional army.

As a militia brigadier general, Marion cooperated with Nathanael Greene's Continental forces. In 1781 he worked with Henry Lee against British posts, including Fort Watson and Fort Motte, and contributed to the wider campaign that reduced British control of the interior. Fighting in South Carolina was also a civil conflict among neighbors, marked by reprisals and competing claims to loyalty. The later image of the Swamp Fox should not conceal that setting or make him the sole author of the southern victory.

Marion continued public service after the war, sitting in the state senate, holding a peacetime military post, and participating in the 1790 state constitutional convention. He resumed plantation life and owned a substantial number of enslaved people, an essential qualification to accounts celebrating his struggle for liberty. He retired from militia command in 1794 and died the following year. Early biographies, especially the version shaped by Mason Locke Weems, mixed documented service with romanticized anecdotes. He sustained resistance and coordinated local warfare with the broader campaign.