Maud was born in Mankato, Minnesota on 214 Center Street, the daughter of shoe store owner Tom Hart and Stella Palmer Hart. Maud was the middle child; her sisters were Kathleen (Julia in the Betsy-Tacy books) and Helen (book character, Margaret). Maud started writing as soon as she could hold a pencil. She wrote in her high school's essay contest during her junior and senior years. Maud was baptized in a Baptist church, but joined the Episcopal church as a teenager. She went on to the University of Minnesota but took a leave of absence to go to California to recover from an appendectomy at her maternal grandmother's home. It was while in California that she made her first short story sale - to the Los Angeles Times Magazine. She returned to the U of M and worked for the Minnesota Daily. She did not graduate from college. While spending a year in Europe in 1914, Maud met Paolo Conte, an Italian musician (who later inspired the character Marco in Betsy and the Great World).
She married Delos Lovelace when she was twenty-five years old. Delos and Maud met in April 1917 and were married on Thanksgiving Day the same year. They lived apart until 1919, however, due to Delos' military service in the First World War.
They divided their time between Minneapolis and New York (including Yonkers and Mount Vernon) for several years. After 1928, they lived in New York permanently until their retirement in Claremont, California. They had one daughter, Merian -- who was named for Delos's friend Merian C. Cooper (Delos had written the novelization of the movie "King Kong", directed by Cooper).
Her first book was The Black Angels, which was published in 1926 and is a historical novel set in Minnesota. She wrote several more historical novels, including the successful Early Candlelight in 1929.
She is best known for her books for children. The Betsy-Tacy series started in 1938 after Lovelace told stories about her childhood to her daughter Merian (1931-1997). The first book in the series, Betsy-Tacy, was published in 1940, and the last book, Betsy's Wedding, was published in 1955. The first four books increase in reading difficulty so that the child can grow up along with Betsy-Tacy. The Betsy-Tacy books take place mostly in the fictional town of Deep Valley, Minnesota, which is based on Mankato. There are also three loosely connected books set in Deep Valley, Winona's Pony Cart,Emily of Deep Valley, and Carney's House Party, in which Betsy and Tacy have minor roles. The series has been enduringly popular. The city of Mankato declared Betsy-Tacy Day on October 7, 1961.
Lovelace spent her later years in California, where she died in 1980. She is buried in the Glenwood Cemetery in Mankato, with a monument dedicated to her. The Maud Hart Lovelace Book Award was established in 1980. Each year, a group of nominees are chosen in two categories: grades 3-5 and grades 6-8. Children who have read at least three books in the relevant category cast a vote for their favorite.
Details about her life and work can be found in The Betsy-Tacy Companion by Sharla Whalen.