The battle over the Princeton Battlefield may be over.

Preservationists have reached a deal with the owner of a parcel of land near the historic battlefield in New Jersey to sell part of the land to the state instead of developing faculty housing.

For nearly 10 years, the Institute for Advanced Study had been making plans to develop on 21 acres, which historians say is Maxwell's Field, the site of Gen. George Washington's strategic attack on British soldiers during the Revolutionary War.

The Princeton Battlefield Society spent years challenging the development, eventually gaining the support of the Civil War Trust, a national organization that preserves American battlefields.

The Civil War Trust reached an agreement with the Institute for Advanced Study to buy 14.85 acres for $4 million and then turn the land over to the state New Jersey. The Institute will retain 5.5 acres to build housing.

"This is a classic win-win solution," said Jim Campi, spokesman for the Civil War Trust. "The institute is able to build the faculty housing it needs, but we're able to protect most of Maxwell's Field, fully 60 percent of it."

The institute — where Albert Einstein once taught — was shovel-ready; it had acquired all the necessary approvals to begin construction. Finance director John Masten said the Civil War Trust had the negotiation abilities and the financial resources to make the Institute change its plans at the eleventh hour.

"Having been approved, we were obviously eager to move ahead," said Masten. "But part of our approach to this project we hadn't been able to return to, and that was to have a good working relationship with all of the interested parties and focusing on the needs of the battlefield."

Instead of eight townhouses and seven plots for individual houses spread over the whole acreage, Masten said the institute will build a cluster of 16 townhouses in a dense development on a quarter of the space.

The Princeton Battlefield Society had been going after all 21 acres of Maxwell's Field. This is a compromise, but one's it's happy to make.

"We hope to work with our neighbors and the town of Princeton and the state of New Jersey to turn the land into a larger open space for the people of Princeton, and show the historic value of what happened on this land," said Roger Williams, society board member.

The society has pending legal action against the institute, which Williams said it will no longer pursue.