Brecht gets inspiration for the title and idea of Mother Courage from a seventeenth-century text by the German author Hans Jakob Christoffel von Grimmelshausen. Written in 1669, the text is a novel called Trutz Simplex, oder Die Ertzbetrügerin und Landstörtzerin Courasche ("Trutz Simplex, or Courage, The Notorious Crook and Vagabond").
Grimmelshausen is better known as the author of Simplicius Simplicissimus (1668), a satirical novel written about the Thirty Years' War. Trutz Simplex also takes place during the war, recording the adventures of a woman named "Courasche" (Courage) who leaves her village in Bohemia and, like Mother Courage, makes a living following armies around Europe.
While there are some superficial similarities between Mother Courage and Trutz Simplex, they definitely stop there. Probably the most important reason why the title refers to a seventeenth-century novel is that, well, the play also takes place in the seventeenth century.
Okay, that one sounds a like a cop out. But really, as we explain in our "Writing Style" section, Brecht knows what he's doing when he sets his play in an unfamiliar historical period. He wants to puzzle and disorient us on purpose, so that we focus on the issues, not the drama. And alluding to an arcane author like Grimmelshausen can only further our disorientation.
Also, by adding "and Her Children" to the title, Brecht solidifies the important—yet secondary—role the three children play in the story. Mother Courage's three children each represent different virtues (Swiss Cheese is honesty, Iliaf is boldness, and Kattrin is sacrifice). Think along the lines of "Snow White and the Seven Dwarves"—each dwarf represents a different virtue. Much like our favorite Disney Princess, Mother Courage must grapple with the three virtues her children represent over the course of the play, ultimately rejecting each one. She lies when she is asked to identify Swiss Cheese's body, she shies away from making a complaint when she is unfairly fined, and she chooses profits over sacrifice again and again.