Poplar Grove began as a sugar plantation in the 1820s when James McCalop combined several smaller tracts of land. The principal residence was originally built as the Banker's Pavilion at the World's Industrial and Cotton Centennial Exposition of 1884-85 in New Orleans, a Victorian structure designed by architect Thomas Sully with oriental motifs popular during the Aesthetic Movement period. Moved by barge to Poplar Grove in 1886, it became the home of sugar planter Horace Wilkinson, a prominent business and civic leader. Joseph L. Harris acquired Poplar Grove in 1885, Wilkinson managed the plantation for Harris, and then purchased it in 1903. Originally 1,438 acres, Poplar Grove was a thriving agricultural operation with its own sugar mill, workers' quarter, church, railroad, mule and hay barns, corn crib, and commissary, and its mill produced raw sugar and molasses until 1973.