McLachlin was born in Pointe-Fortune[1] in Lower Canada on 17 July 1808, to Hugh McLachlin and Janet (née McLean).[2] He had many siblings; Mary (born 1795), Alexander (b. 1796), John (b. 1798), Flora (b. 1800), Janet (b. 1802), Dorothy (b. 1804), Ann (b. 1806), Catharine (b. 1810), William (b. 1813), Hugh (b. 1816), Sara (b. 1820), and Christina. The family lived in Argenteuil, Lower Canada.[2]
McLachlin married Maria Harrington in 1837.[1] They had eight children together; Jessie, William, Harriet, Hugh, John, Daniel, Eric, and Claude.[3] The family moved to Arnprior in 1857.[1]
In 1851, he relocated his timber business to the nearly deserted village of Arnprior, using the power of the Madawaska River to operate his mills.[1] He also helped promote the development of the settlement there. He had bridges built, helped to bring people in, and took a leading role in promoting public improvements. Two of these involved the Madawaska River Improvement Association (later Company) and a wagon road on the Madawaska River from Arnprior to the Long Rapids. The same year, he was elected to the Legislative Assembly for Bytown; he did not run in 1854 but was elected in 1861 for Renfrew. By 1865, he was running the lumber business with his sons (Hugh, John, and Daniel) under the name "McLachlin Brothers."[1]
In 1867, he was elected by acclamation to the 1st Canadian Parliament for Renfrew South. He resigned from politics and his business in 1869, leaving the business to his sons, who he'd brought into the business in 1865. He died in Arnprior on February 6, 1872.[1]
^ ab(Baptism Record) Archives Nationales du Quebec a Montreal, Canada Quebec District Judiciaire de Montreal, Registres d'Etat Non-Catholique; No. de Projet: QUEB 49010 (Item 2). Montreal St. Gabriel Presbyterian Church, Folio 13, p. 58.
