Maritha was born in Bree from Leila Oakleaf, cook at the mess hall, and Sam Rosethorn, accomplished rat-catcher; she has an older brother, a younger sister and various relatives scattered in Bree and other villages.

She gets wed at nineteen years old, with the constructin labourer Kenneth Willow, and for a good amount of years their life flows smoothly in the daily routine; until the day Kenneth decides to join the Blackwolds, giving up the daily labour for a life of banditry.

Maritha struggles with the "new course" her family has taken: naturally honest and lover of a simpler and more lawful way of life, soon ceases to cope with her husband's shenanigans, and gives him the ultimatum. Needless to say, Kenneth scoffs at his wife's "weakness" and moves out, to go live at the brigands' headquarters.

Thus, the darkest phase of Maritha's life commences: married, yet away from an outcast husband, constantly torn between her love for him and the social shunning that being wed to an outlaw was bringing to her. Maritha doesn't speak gladly of this period, and even less of the one immediately after, when eventually she was given the news that her husband had been caught.

Kenneth sent word to her for a meeting, while in jail, wanting to see her one last time. Nobody knows what he would have wanted to tell her, before the end, because Maritha did not go. He was hung at dawn, the day after.

After the death of her husband, Maritha took back her maiden name of Rosethorn, left the marital house and went back to live with her parents, assisting the old father until his natural death, and then taking over her mother's job in the mess hall when she was too old to work anymore.