When was the octagon house built?

Answer 1

The Octagon House, built between 1798 and 1800, was designed by Dr. William Thornton, the architect of the U.S. Capitol, and completed by 1800. Colonel John Tayloe, for whom the house was built, owned Mt. Airy plantation, located approximately 100 miles south of Washington in Richmond County, Virginia. Tayloe was reputed to be the richest Virginian plantation owner of his time, and built the house in Washington at the suggestion of George Washington. In 1814, Colonel Tayloe offered the use of his home to President and Mrs. Madison for a temporary "Executive Mansion" after the burning of the White House by the British.