BRISTOL — Linden Place, a Federal-style mansion and museum that is a centerpiece of downtown, has received a $1-million gift from the estate of the late Alfred J. Shepherd.

The donation, announced last week, is the largest in the history of the nonprofit museum, according to executive director James B. Connell. The money has been invested and the interest it generates — an estimated 7 percent to 10 percent annually — will be used to pay for repairs and renovations to the 1810 mansion and its ancillary buildings.

The museum recently repaired the four Corinthian columns framing the front entrance and is facing a $25,000 expense to install a new sprinkler system inside the main house, and $275,000 to replace the slate roof atop the ballroom.

“We still have much to do to maintain the estate,” Connell said.

The mansion on Hope Street was built by Gen. George DeWolf and was later owned by Samuel P. Colt, the founder of Industrial Trust, which became Fleet Bank.

Shepherd, a Bristol resident, spent 22 years in the Navy, rising to the rank of lieutenant commander, and later became a counselor at what is now Roger Williams University. He was a philanthropist who supported many local causes and was married to two DeWolf descendants.

Last year, a year after Shepherd died at the age of 90, the museum was notified of the donation. Shepherd specified that the money was to be used as an endowment for capital projects.

Connell spoke to Shepherd about Linden Place several times before his death, but he said relatives of the late philanthropist should be given credit for making him aware of the museum’s financial needs.

“We are very grateful,” Connell said.

akuffner@projo.com