The construction of fortifications at Kingston was, in part, a response to the American construction of the Erie and Oswego canals. The Americans had built these waterways for primarily economic reasons, but they also had the potential to be used to transport and supply large numbers of troops along the Canadian frontier.
The Canadian response was to build the Rideau Canal to improve communications between Upper and Lower Canada and construct extensive fortifications at Kingston Harbour. In 1828, Governor Sir James Kempt proposed that the harbour be fortified with the construction of six forts, and he submitted detailed plans to the British government the following year. However, the high cost of the Rideau Canal precluded the complete implementation of Kempt's plans.
As a result, only Fort Henry was built. Construction, began in 1832, was completed in 1836 at a cost of £72,747. In 1841, the fort was further strengthened with the construction of an additional battery (£9,737).