Archibald Buchanan Jnr was the son of Archibald Buchanan of Catrine in Ayrshire, a partner in the firm of James Finlay & Co which owned several cotton mills including Catrine Works. Archibald Jnr carried on with managing the mill after his father's death. In 1882 he bought Curriehill House near Riccarton, Edinburgh. His daugher Julia married Sir Henry Gibson-Craig in 1870. The records include business accounts and correspondence, personal accounts and family records.