In 1862 gold was found at Brewery Creek in the Cromwell Gorge by miners Hartley and Reilly. The find sparked a gold rush that saw many Central Otago towns establish and survive to the present day.
Up until mid 1863 Cromwell, situated at the junction of the Clutha and Kawarau rivers, was known as The Junction'. The town was surveyed by J. Aitken Connell in 1863 and its official name was given to it by the Lands Office in Dunedin. The survey completed, the Provincial Government confirmed the name of Cromwell following Connell's survey plan.
In June 1866 the population had reached 470 and it was then that a meeting was held to petition the government to form Cromwell into a municipality. As a result Cromwell Borough Council came into being and with a grant from government of five hundred pounds, Captain Jackson Barry, the first Mayor elect, and his four councillors commenced the responsibility of determining the future of the borough.
