The son of a border farmer, he became steward and amanuensis to Walter Scott, and was the author of a well-known ballad, Lucy's Flittin.
James Hogg, whose mother was his distant cousin, was employed at Blackhouse for ten years, and formed a lasting friendship with Laidlaw.
After two unsuccessful attempts at farming, in Peeblesshire and Midlothian, Laidlaw in 1817 became steward to Sir Walter Scott at Abbotsford.
In 1819, when Scott was recovering from an illness, Laidlaw and Ballantyne wrote to his dictation most of The Bride of Lammermoor, and subsequently A Legend of Montrose, and nearly all Ivanhoe.
St. Ronan's Well may have been due to Laidlaw's suggestion that Scott should devote a novel to "Melrose in July 1823", according to John Gibson Lockhart.