Marilyn Monroe’s Childhood. Marilyn Monroe was born Norma Jeane Mortenson on June 1, 1926, in Los Angeles, California. Her mother, Gladys Pearl Baker, worked as a film negative cutter in Hollywood but struggled with severe mental illness, which left Norma Jeane without stable parental care. Foster Homes and Orphanage (1926-1935) Norma Jeane never knew her father, and her mother was institutionalized due to schizophrenia when she was still a toddler. As a result, she spent most of her childhood i