After the Seminole War ended in 1842, the Manatee River valley frontier opened to settlement, and Major Robert Gamble and other sugar planters established plantations there, with a dozen producing for the New Orleans market by 1845. Built principally of native materials between 1845 and 1850, the Gamble Mansion was an outstanding example of ante-bellum construction and reflected pioneer ingenuity and craftsmanship. The plantation included 3500 acres, numerous outbuildings, slave quarters, and a wharf from which sugar and molasses were shipped by schooner and steamboat. During the Civil War, the mansion was the home of Captain Archibald McNeill, a Confederate blockade runner, and in May 1865 Judah P. Benjamin, Confederate Secretary of State, took refuge there while escaping Federal troops after the Confederacy's defeat. The Gamble sugar mill, one of the South's largest, was destroyed by Union raiders in 1864, and the mansion was rescued from decay in 1923 by the Judah P. Benjamin Chapter of the United Daughters of the Confederacy.