Background
Mackenzie was born near Nelson, Lancashire, England, the eldest of the 11 children of Alexander Mackenzie, a Scottish contractor, and Mary née Roberts.
Mackenzie was born near Nelson, Lancashire, England, the eldest of the 11 children of Alexander Mackenzie, a Scottish contractor, and Mary née Roberts.
He started his career as an apprentice weaver but changed to civil engineering, becoming a pupil of a lock carpenter on the Leeds and Liverpool Canal in 1811. He continued his training on a dry dock at Troon harbour, on Craigellachie Bridge and as an agent on the Edinburgh and Glasgow Union Canal. In 1822 he became an agent for the completion of the Gloucester and Berkeley Canal.
Soon after this he was appointed resident engineer for Thomas Telford"s Mythe Bridge at Tewkesbury, then resident engineer to the improvements to the Birmingham canals, again under Telford.
Following this he returned to contracting, his profitable contracts including tunnels on the Liverpool and Manchester Railway between Edge Hill and Lime Street, and contracts for the Grand Union, North Union, Midland Counties and Glasgow, Paisley and Greenock railways. Non-railway contracts included Liverpool Haymarket, the Manchester and Sheffield Junction Canal and the Shannon navigation.
In 1840 Mackenzie was invited by Joseph Locke to tender for works on the Paris to Rouen railway. He tendered jointly with Thomas Brassey and together they were granted the contract.
When this was complete he built more railways in France, Spain, the Italian states and Belgium.
Also in partnership with Brassey he built further railways in France, England, Wales and Scotland. Mackenzie also made investments, which included ironworks in Wales and France, housing in Liverpool and estates in Scotland.