211 Commonwealth is located on the north side of Commonwealth, between Exeter and Fairfield, with 207 Commonwealth to the east and 213 Commonwealth to the west.

211 Commonwealth was designed by Rotch and Tilden, architects, and built in 1883-1884 by George G. Nichols, mason, as the home of William Powell Mason, Jr., and his wife, Fanny (Peabody) Mason. He purchased the land for the house on June 1, 1882 from the Commonwealth of Massachusetts.

Click here for an index to the deeds for 211 Commonwealth, and click here for further information about the land between the north side of Commonwealth and Alley 426, from Exeter to Fairfield.

By the 1884-1885 winter season, William and Fanny (Peabody) Mason had made 211 their home. They previously had lived at 75 Beacon. They also maintained homes in Beverly and in Walpole, New Hampshire.

Educated as a lawyer, William Mason managed his family property and was a director of numerous companies.

In the 1890s, a music room — designed by Arthur Rotch — was added at the rear of the house.  The exact date of the addition is not known, but based on the Bromley insurance maps, it appears to have been added sometime between 1890 and 1895 (it does not appear on the 1890 Bromley map but does appear on the 1895 map). In 1891, pianist and composer Ferruccio Busoni gave a concert at 211 Commonwealth, and it appears likely that this was soon after the new music room was completed.

Fanny (Peabody) Mason died in May of 1895. After her death, William Powell Mason and their only surviving child, Fanny (Fannie) Peabody Mason, traveled in Europe for two years and then continued to make 211 Commonwealth their home.

William Mason died in June of 1901. Fanny Mason continued to live at 211 Commonwealth and to maintain homes in Beverly and Walpole. In September of 1901, she purchased the stable at 333 Newbury, which she continued to own until 1922.

From about 1909, Fanny Mason was joined at 211 Commonwealth by Miss Alice Thevin, a painter and lecturer on fine arts.  Miss Thevin continued to live there until her death in February of 1937.

Fanny Mason had a deep interest in music and the music room at 211 Commonwealth was the site of numerous performances by noted artists. Among the artists who performed either at 211 Commonwealth or at her homes in Beverly and Walpole were Ignacy Paderewski; Arthur Rubinstein; the Alfred Cortot-Jacques Thibaud-Pablo Casals trio; Emma Calvé; and Egon Petri.  In later years she worked in close collaboration with pianist Paul Doguereau, who organized many of the recitals.

Bainbridge Bunting’s Houses of Boston’s Back Bay includes several photographs of the interior of 211 Commonwealth as it appeared when it was Fanny Mason’s home.

Fanny Mason died in August of 1948. In her will, she left a trust for musical enterprises to be overseen by Paul Doguereau. The trust funded continuation of the Peabody Mason Concerts at various locations in Boston and, in 1981, initiated the Peabody Mason International Piano Competition.

On April 18, 1949, 211 Commonwealth was purchased by Newman Preparatory School. In June of 1949, it filed for (and subsequently received) permission to convert the property into a school, library, and private chapel.

The school continued to occupy 211 Commonwealth until about 1951.

On February 5, 1951, 211 Commonwealth was acquired from the Newman School by St. Coletta School by the Sea. The school, founded in 1947 to serve mentally retarded children, was located in Hanover and operated by the Sisters of St. Francis of Assisi. 211 Commonwealth became the Archbishop Cushing Educational Clinic, a remedial reading center, and, from about 1962, also served as a convent for the Sisters.

On July 11, 1967, 211 Commonwealth was acquired from the St. Coletta School by Chamberlayne School and Chamberlayne Junior College located at 128 Commonwealth. It used 211 Commonwealth as a school, primarily to meet overflow requirements from its other Back Bay facilities. Chamberlayne filed for bankruptcy in September of 1974 and on June 16, 1975, 211 Commonwealth was transferred to Bernard P. Rome of Newton, trustee in bankruptcy.

In December of 1975, Chamberlayne filed for (and subsequently received) permission to convert the property into professional offices and two apartments, noting that the firm of Atwood, McGrath, and Wright had entered into a purchase and sale agreement for the property subject to the change in use.

On July 28, 1976, 211 Commonwealth was purchased from Bernard Rome by David M. Wright, trustee of the Mason Mansion Nominee Trust, on behalf of the law firm. The firm’s senior partner, Jacob M. Atwood, subsequently became trustee and on May 21, 1985, the trust transferred the property into his name.

211 Commonwealth remained the law offices of Atwood, McGrath, and Wright (later Atwood and Cherny) until 1998.

On February 26, 1998, 211 Commonwealth was purchased from Jacob Atwood by the Fairmont Company LLC. In November of 1998, it applied for (and subsequently received) permission to convert the property back into a single-family dwelling.

211 Commonwealth became the Boston home of John Reime Roy and his wife, Mary Louise (Quigley) Roy. They also maintained a home in Cohasset. He was founder of Air-Tek, an air pollution control company, and of the Intercontinental Energy Corporation, owners and operators of power plants the North East.

John Roy died in August of 1999. 211 Commonwealth remained Mary Louise Roy’s Boston home until her death in March of 2004.

On February 4, 2014, Michael A. Bass, trustee of The 211 Commonwealth Avenue Nominee Trust, purchased 211 Commonwealth from the Fairmont Company, LLC. On July 30, 2017, he transferred the property to himself as trustee of The Zeal Realty Trust II.

211 Commonwealth was assessed as a single-family dwelling in 2023.