Byrnside-Beirne-Johnson House, also known as "Willowbrook," is a historic home located near Union, Monroe County, West Virginia.

After 1855, it was enlarged to a large 2+1⁄2-story, five-bay, T-shaped dwelling with a two-story rear wing.

He amassed considerable wealth and power in the area, for example, being taxed for 3,750 acres in 1783 (1783 Greenbrier County Land Roll).

Five separate pension applicants mentioned being stationed at Byrnside's Fort (Bradshaw, Christy, Kincaid, Swope, Wincleback) between 1776 and 1781.

This article about a property in Monroe County, West Virginia on the National Register of Historic Places is a stub.