Mother Maria was born in Latvia in 1891. Like many of the pre-Revolutionary Russian intelligenstia, she was an atheist and a political radical in her youth, but gradually came to accept the truths of the Faith. After the Revolution, she became part of the large Russian emigre population of Paris. There she was tonsured as a nun by Metropolitan Evlogy, and devoted herself to a life of service to the poor. With a small community of fellow-believers, she established 'houses of hospitality' for the poor, the homeless, and the alcoholic, and visited Russian emigres in mental hospitals. In 1939 Metropolitan Evlogy sent the young priest Fr Dimitry to serve Mother Maria's community; he proved to be a partner, committed even unto death, in the community's work among the poor. When the Nazis took Paris in 1940, Mother Maria, Fr Dimitry, and others of the community chose to remain in the city to care for those who had come to count on them. As Nazi persecution of Jews in France increased, the Orthodox community's work naturally expanded to include protection and care of these most helpless ones. Father Dimitri was asked to provide forged certificates of baptism to preserve the lives of Jews, and always complied. Eventually, this work led to the arrest of Mother Maria, Fr Dimitri, and their associates. A fragment survives of the Gestapo's interrogation of Fr Dimitri:

Hoffman: If we release you, will you give your word never again to aid Jews?

Klepinin: I can say no such thing. I am a Christian and must act as I must. (Hoffman struck Klepinin across the face.)

Hoffman: Jew lover! How dare you talk of helping those swine as being a Christian duty! (Klepinin, recovering his balance, held up the cross from his cassock.)

Klepinin: Do you know this Jew? (For this, Father Dimitri was knocked to the floor.)

"Your priest did himself in," Hoffman said afterward to Sophia Pilenko. "He insists that if he were to be freed, he would act exactly as before."

Mother Maria, Fr Dimitri, and several of their colleages, were sent to the Nazi concentration camps (Mother Maria to Ravensbruck, Fr Dimitri to Buchenwald) where, after great sufferings, they perished. It is believed that Mother Maria's last act was to take the place of a Jew being sent to death, voluntarily dying in his place.

A full account of their life and death is given on the site of the Orthodox Peace Fellowship.

Mother Maria and her companions were glorified by the Patriarchate of Constantinople in 2004.