Dress designer Sophie Rosenberg was born in Odessa, Russia, on December 21, 1888, to Benjamin and Leah Daschew. At age twenty she immigrated to the United States and came to New York City, where she was to live the rest of her life. Shortly after her immigration, on April 20, 1908, she married Abraham Jacob Rosenberg.

Her first job in the United States was as a forelady at the Eureka Dress Company in 1908. By 1916, she started her own dress company at 161 West 44th Street. In 1926, the partnership of S. Goodstein and Sophie Rosenberg became known as Sonia Inc., using Rosenberg’s middle name as title to the company. Later that year, Sonia Inc. became formally known as Rosenberg-Goodstein Inc., only to be changed to Sonia Rosenberg Inc. by 1929. The final and most remembered name of Sophie Rosenberg’s company came to be Sonia Gowns Inc. in 1935, when she entered into the business with Gloria Morgan Vanderbilt.

Under the terms of this business alliance, Gloria Vanderbilt was president of the company, and her twin sister, Thelma Furness, its vice president, while Sophie Rosenberg was secretary, and Jacob Rosenberg was treasurer. They were all to have equal authority in the management of the company. Unfortunately, this business alliance was short-lived and unprofitable for all parties involved by 1938. The New York Times reported that Gloria Vanderbilt sued to close the gown shop and reported losing all of her initial $40,000 investment, plus an additional $10,000 requested by Rosenberg for the business.

Though her business venture with the Vanderbilt family was brief, she never left the dress design business, and within a few short years, in 1944, she went into business once again, retaining the name of Sonia Gowns Inc. This time, she made herself president of the company and was in partnership with Ethel D. Arkin and George Arkin at 25 West 57th Street in New York. Rosenberg remained there until she closed the shop in 1956 at age sixty-eight.