Since her birth, Marie was the legitimate heiress of the Lordship of Montpellier, because a clause of the marriage contract of her parents established that the firstborn child, boy or girl, would succeed in Montpellier on William VIII's death. In April 1187, William VIII repudiated Eudokia Komnene and married a certain Agnes, a relative of the Kings of Aragon. She bore him eight children, six sons and two daughters. Although Eudokia entered in a convent in Aniane as a Benedictine nun, William VIII's second marriage was declared invalid and all the children born from this union declared illegitimate, so Marie remained as the undisputed heiress of Montpellier. Marie married Viscount Raymond Geoffrey II of Marseille, also named Barral, in 1192 or shortly before, but was widowed at the end of that year. Her second marriage, in December 1197, was to Count Bernard IV of Comminges, and at the insistence of her father, Marie renounced her rights over Montpellier in favor of her eldest half-brother William, son of Agnes. From her marriage with Bernard IV, Marie had two daughters, Mathilde and Petronille. The marriage was, however, notoriously polygamous and was finally annulled in 1201. With this annulment, Marie was once more heir to Montpellier, but her father never recognized her and openly acknowledged his son William IX as his heir. William VIII died in 1202. Marie's half-brother William IX had taken control of the city, but she asserted her right to it. On 15 June 1204 Marie married Peter II of Aragon and thanks to a revolt against William IX, she was recognised as Lady of Montpellier. From her marriage with Peter II, Marie gave birth two children: Infanta Sancha and Infante James, the future King James I the Conqueror. Peter II immediately attempted to divorce her, hoping both to marry Maria of Montferrat, Queen of Jerusalem, and to claim Montpellier for himself. Marie's last years were spent in combating these political and matrimonial manoeuvres. Pope Innocent III finally decided in her favour, refusing to permit the divorce. Marie died in Rome on her way back to Aragon, and Peter II a few months later at the Battle of Muret. Marie and Peter II's only surviving child, King James I, inherited Aragon and Montpellier.
