Sonia Greene was born as Sonia Haft Shafirkin or Sonia Shaferkin Haft into a Jewish family living in the Ukraine, then part of the Russian Empire. Her birthplace may have been Ichnia, Ukraine, or Konotop, Chernigov Province. Her father apparently died when she was a child, and her mother emigrated to the USA, leaving young Sonia and her brother in an English boarding school. Sonia joined her mother in America in 1892, after her mother had remarried to a shopkeeper. In 1899, at age 16, Sonia married Samuel Greene, a Russian immigrant 10 years her senior. She had two children, a son who died at three months of age and a daughter, Florence Carol (later a journalist known as Carol Weld), born in 1902. The marriage seems to have been turbulent; Samuel Greene died in 1916, apparently by his own hand. At age 33, Greene was an independent middle-class woman, unusual for that era. She worked as a milliner at a department store before opening her own hat shop. She was able to rent a house for herself and her daughter in the upscale Flatbush neighborhood of Brooklyn. She was interested in writing, and her salary allowed her to donate money to several amateur press publications, and to travel to amateur press conventions. In 1921, she met H. P. Lovecraft at an amateur press convention in Boston. The following year, she issued The Rainbow, an illustrated fanzine containing contributions by many leading writers. After their marriage in 1924, Lovecraft relocated to Brooklyn and moved in with her. Then Greene lost her hat shop and suffered poor health. Lovecraft could not find work to support them both, so Greene moved to Cleveland for a job, and Lovecraft lived by himself in Brooklyn. In the last year or so of their marriage, Greene lived on the road, traveling for her job. She sent Lovecraft a weekly allowance that helped him pay for a tiny apartment in Brooklyn Heights where she stayed one or two days out of the month. He returned to living in Providence, Rhode Island and the couple agreed to a divorce which was never fully completed. Greene's best-known story was "The Horror at Martin's Beach", a.k.a. "The Invisible Monster," which was revised and edited by Lovecraft for publication in Weird Tales (1923). In the 1930s, Greene wrote a play called "Alcestis", in which the Prologue was written in Lovecraft's hand. It remained unpublished until the mid-1980s, when it was issued in a facsimile holograph edition of 200 copies by The Strange Company as by H. P. Lovecraft and Sonia Greene. Some Lovecraft scholars consider that the play is probably all Greene's work. Her marriage to Lovecraft ended, Greene moved in 1933 to California, where she married a Dr. Nathaniel Abraham Davis of Los Angeles in 1936, technically a bigamous union although she didn't know it until much later in life.