Margaret March, known as Marmee, serves as the matriarch of the March family in Concord, Massachusetts. She manages the household during her husband's service as a Union Army chaplain. Her background involves a transition from wealth to poverty after her husband lost his fortune loaning to an unreliable friend. This experience required her to master household management skills and shaped her values of simplicity and contentment without material wealth.

Marmee acts as the moral anchor for her four daughters—Meg, Jo, Beth, and Amy—and extends maternal care to their neighbor, Theodore "Laurie" Laurence. She emphasizes self-improvement, charity, and resilience, using daily experiences as teaching tools, such as allowing a week of idleness to demonstrate the value of work. Her parenting blends warmth with principled guidance, encouraging her daughters to marry for love and fulfillment over financial security.

Despite her calm exterior, Marmee privately confides in Jo about a daily struggle with anger, controlled through patience and discipline. Her charitable work aids impoverished neighbors like the Hummel family and supports Union soldiers, reflecting her belief in generosity across social classes.

She is described as tall and maternal, with a dignified bearing despite modest clothing, grayish-brown hair, and hazel eyes. Later, she becomes a grandmother to Meg's children Daisy and Demi, Amy's daughter Elizabeth "Bess" Laurence, and Jo's sons Robert "Rob" and Theodore "Teddy" Bhaer, remaining the family's emotional cornerstone. Her daughters emulate her values in their own marriages and households.