It takes a while to pull a room together until it’s right. Harriet Flower Mathews took nine years to complete her parlor at Butler Greenwood plantation in St. Francisville.

She bought the 537?8 yards of carpet with its eternal bunches of red roses in 1852, the $200 golden drapery in 1859. Finally, on Jan. 25, 1861, a store in Connecticut billed Mathews $467.04 for the fashionable rococo revival furniture suite with a marble-top table, rosewood sofa ($77) and matching chairs upholstered in a tufted salmon-hued silk. The next day, Jan. 26, Louisiana seceded from the Union.

Life changed radically for the widow of a Louisiana Supreme Court justice and her descendants, but the furniture, carpet and drapes sat in place in the house until last December. The New Orleans Museum of Art acquired the parlor pieces last year and set them up as they were at Butler Greenwood. They are the main attraction of “A Louisiana Parlor: Antebellum Taste & Context,” on view through Oct. 11.

Anne Butler is happy to tell the story. A youthful 71, soft-spoken with a whimsical sense of humor, Butler is the seventh generation of her family to live in Butler Greenwood, which she still operates as a bed and breakfast. She stopped giving tours after 23 years. “I decided I had just about all the joys of dealing with the traveling American public that I could stand.” she said. “People appreciated the things less and less. They’d say, ‘This is cute,’ and I’d think, ‘This is not cute.’ ”

A writer, whose most recent book is “Images of America: St. Francisville and West Feliciana Parish,” Butler is passing the house to her son, but said, “I despaired of what to do with the furniture.” She hoped a museum would buy it. No one had any interest.

Enter Paul Haygood, a New Orleans lawyer intrigued by the histories of antique objects. He helped found the nonprofit Classical Institute of the South to inventory and study such items, partnering with NOMA, the Historic New Orleans Collection and the Louisiana State Museum, among others.

The Institute began work in 2011 in St. Francisville, and Haygood arrived at Butler Greenwood with interns from Winterthur Museum, a repository for Americana and decorative arts in Delaware. They spent weeks cataloging bills of sale, census records, letters, data on slaves, everything. Scholars at Winterthur were amazed so much was intact and that the furniture and carpets were in such good shape, Butler said.

Mel Buchanan, 35, who received her master’s at the University of Delaware’s Winterthur Program, joined the NOMA staff in the fall of 2013 as RosaMary curator of decorative arts and design. A colleague connected her with Haygood. She delved quickly into Butler Greenwood’s parlor, which she said “is one of the South’s best examples of a pre-Civil War Louisiana interior.” Documents found there and at the LSU Library Special Collections tell a very human story.

In the 1860 census, before the Civil War started, Harriet Mathews was 65 and worth $100,000. She owned 96 slaves. A written record from 1866 lists 26 free men still living on the plantation. By the 1870 census, Harriet had $5,000 in assets. She died in 1873.

A nephew wrote in 1861 that he and his fellow Confederate soldiers were 18 miles from Alexandria, where there were 30,000 federal troops.

A document in 1862 referred to “seven Negroes pressed into service” of the Confederate army.

There were more letters from the Connecticut furniture store. The first, dated April 24, 1861, says, “We are in great need of funds. We are aware that troublesome times are come to all parts of our country, but … .”

The bill remained unpaid in 1867, when a stern letter added five years of interest, making the new furniture invoice $630.49.

Also in the exhibit are borrowed portraits of the family and examples of other popular decorative styles in the 19th century.

Anne Butler, looking pleased at the public opening last Friday, said, “It’s so nice the parlor has come to New Orleans.”

Missing, but thanked by Butler and Buchanan, with sorrow in their voices, was Paul Haygood. He died June 13.