Georgia's highest court says, Savannah's Christ Church belongs to the national Episcopal Church.
The ruling sets up the possibility of an emotional Christmastime eviction and homecoming in a four year old case.
Georgia's oldest church split in 2007 over theological issues.
Some of its members said the national church was straying from the Bible when it ordained an openly gay bishop.
They claimed the historic building and other property valued at nearly $3 million.
Other members started worshipping elsewhere but fought to return to the sanctuary.
Frank Logue of the Savannah Episcopal Diocese says, the ruling means the group meeting in the church building will have to move out.
"We expect that they will be gracious in this and that we will work together on how to turn over the property," Logue says. "We certainly want to do the same and make room for them to move on in an orderly way."
A lower court would have to order the eviction.
That could take a few weeks.
Logue says, Christ Church members who stayed with the national church feel both joy at the prospect of returning and sorrow at the prospect of evicting their church brothers.
The split locally has divided Episcopal families and friends in Savannah, just as the wider split in the church has divided Anglicans nationally and internationally.
Church warden David Reeves says, no matter what happens, the group currently meeting at Christ Church won't be without a home.
"Christ Church has a Plan B that is in place," Reeves says. "As soon as we are told that we will have to leave the church building, we're going to begin our worshipping at Independent Presbyerian Church just a few blocks down the street."
Christ Church officials say, they're considering an appeal to the US Supreme Court.