Alexander McKay (1832-1922), a Scottish immigrant, was a miner and businessman in Virginia City, Montana. Records (1857-1922) include correspondence, financial records, legal documents, and court papers for McKay's business interests including flour mills and mining claims. There are subgroups for Elling, Baker McKay (1887-1911); Mill Creek Mills (1878-1898); Caroline Hanson McKay (1877-1911); and Mary McKay Herhold Bothwell Swanze (1876-1925).