Giles County was formed from Montgomery, Monroe (now in West Virginia), and Tazewell Counties in 1806 and was named for William Branch Giles, a United States senator from Virginia who later became governor. North of here, the county's first court was held on 13 May 1806 at the house of George Pearis. The new county seat, Pearisburg, was established in 1808 after Pearis donated 53 acres of land for the town. A temporary log structure was built by 1807 to house the court until a permanent stone courthouse was built around 1810, and that building was later replaced by the current courthouse erected in 1836.