256 Marlborough was built in 1887 by Silas Whiton Merrill, a builder, for speculative sale, one of three contiguous houses (254-256-258 Marlborough). He is shown as the owner and builder on the original building permit applications for all three houses, each dated April 14, 1887. He also is shown as the owner on the final building inspection reports for all three houses, all dated May 9, 1888, with David L. Rand, mason, shown as the builder. Neither the applications nor the inspection reports indicate an architect. Silas Merrill is also shown as the owner of all three houses on the 1888 Bromley map.
During the 1889-1890 winter season, 256 Marlborough was the home of Edwin Holbrook Sampson, a paper manufacturer and dealer, and his wife Julia Verlinda (Wiltberger) Sampson. They previously had lived at the Hotel Oxford (southeast corner of Exeter and Huntington). He is shown as the owner of 256 Marlborough on the 1890 Bromley map. By the 1890-1891 season, they had moved back to the Hotel Oxford.
By the 1890-1891 winter season, 256 Marlborough was the home of Elizabeth Seaver (Soule) Sweetser, widow of insurance executive Isaac Sweetser. She previously had lived at 19 Monument Square in Charlestown, where she was living when her husband died in August of 1887.
Her son, attorney Isaac Homer Sweetser, and her daughter, Ida Elizabeth Sweetser, lived with her.
Elizabeth Sweetser died in April of 1895.
Isaac Sweetser and Ida Sweetser continued to live at 256 Marlborough. He is shown as the owner on the 1895, 1898, 1908, and 1912 Bromley maps.
During the early 1900s, and possibly earlier and later, their cousin, Helen M. Sampson, was living with them. She was the daughter of their mother’s sister, Mary Chapman Soule, and Sylvanus Sampson.
Isaac Sweetser died in April of 1915. Ida Sweetser continued to live at 256 Marlborough. Isaac Sweetser’s Heirs are shown as the owners on the 1917 and 1928 Bromley maps.
During the 1916-1917 winter season, Ida Sweetser was joined by Susan Jameson (Anderson) Sweetser, the widow of her brother, Frank Eliot Sweetser. Susan Sweetser previously had lived in Brookline with her son and daughter-in-law, attorney Frank Eliot Sweetser, Jr., and Ethel (Walker) Sweetser. By 1918, she had moved back to Brookline.
Ida Sweetser died in May of 1929.
In the summer of 1930, 256 Marlborough was acquired by George H. Holden. The transaction was reported by the Boston Globe on August 24, 1930.
256 Marlborough was not enumerated in the 1930 US Census, and was not listed in the 1930-1932 Blue Books.
By 1933, 256 Marlborough was the home of Mrs. Katherine (Phister) Cowin, the widow of US Army Colonel William Benton Cowin, and two of their children, John Phister Cowin and Miss Jean Cowin.
John Cowin was killed in an automobile accident in August of 1933.
Katherine Cowin and Jean Cowin continued to live at 256 Marlborough during the 1935-1936 winter season, but moved soon thereafter to an apartment at The Colonial at 382 Commonwealth. By 1936, Katherine Cowin was treasurer of the International Institute of Boston at 190 Beacon.
By early 1936, 256 Marlborough was the home of leather merchant Albert F. Gordon and his wife, Sarah V. (Flanagan) Gordon. They previously had lived in Brookline. In February of 1936, Albert Gordon applied for (and subsequently received) permission to remodel the interior to add an elevator. A. F. and S. V. Gordon are shown as the owners on the 1938 Bromley map.
They continued to live at 256 Marlborough until his death in March of 1948.
By 1948, 256 Marlborough was owned by Thomas Diab. In September of 1948, he applied for (and subsequently received) permission to convert the house from a single-family dwelling into a five apartments.
The property changed hands and in September of 1962 was acquired by real estate broker Peter A. Mead. He and his wife, Sara D. Mead, lived in one of the apartments. In 1969, they combined the units on the first and second floors, creating a duplex apartment and reducing the number of units from five to four.
256 Marlborough remained an apartment building, assessed as a four- to six-family dwelling, in 2015.