Above: Southwest corner of 13th and Locust Streets in 1859, Henry B. McIntire, Graphics Collection

In November 1882, Francis Stokes, a lumber merchant and Society member, offered to sell the Society a mansion on the southwest corner of 13th and Locust Streets. The mansion, a three-story stone structure in modified Greek style of architecture, had been constructed by John Hare Powel in 1832. It was the former home of General Robert Patterson, who had served in the War of 1812, the Mexican War, and the Civil War. The mansion, with its gardens, greenhouses and grounds, stretched from 13th to Juniper Streets and half way to Spruce Street from Locust. It was well known and loved in Philadelphia, as Patterson had frequently entertained notable guests including author Charles Dickens, actress Fanny Kemble, and General Ulysses S. Grant.

The Historical Society was enthusiastic about this new site, and within seven weeks raised the necessary funds to procure it. On February 1, 1883, the Historical Society of Pennsylvania purchased half of the original property, including the mansion, for $50,000. While the Patterson mansion was beautiful, it had to be altered to better accommodate the Society and its growing collections. The Society formed a committee to make improvements to the structure. Architect Addison Hutton drew up plans for the construction of a new building on the west side of the mansion—a spacious hall for Society meetings. Hutton also designed a fireproof storage area on the northeastern corner of the property.

Above: Patterson Mansion/Historical Society looking east & Patterson Mansion/Historical Society looking west, Society Photo Collection

The Historical Society of Pennsylvania proudly opened its new facility at 13th and Locust Streets on March 18, 1884. At the first Society meeting in its new home, President Brinton Coxe said: “After fifty-nine years of existence, you now meet under a roof which is your own. You are no longer tenants of another, but proprietors, in your own right, of your own house, on your own soil. The moral and material anxieties connected with a precarious tenure, which were always matters of permanent solicitude are now at an end.”

Above: Historical Society of Pennsylvania with Assembly Hall Annex on the right and fireproof vault on the left, Society Photo Collection