Gordon Drummond was born in Quebec City on 27 September 1772. He was of Scottish descent, the son of Colin Drummond (1722-1776), of Megginch Castle, Perthshire, and his wife Catherine Oliphant of Rossie. His sister married Lord Hervey and his brother married a daughter of John Fane, 9th Earl of Westmorland.

Gordon's father first came to Lower Canada in 1764 as the Quebec agent to the London firm of Sir Samuel Fludyer, Adam Drummond (his brother) & Franks, contractors for victualling the troops in North America. At Quebec, Colin Drummond became a business partner of Jacob Jordan and served as Commissary General, deputy Paymaster General to the Forces in the Province of Quebec and Legislative Councillor. Four years after Colin Drummond's death, in 1780 the family left Quebec and Gordon received his education at Westminster School in England before entering the British army as an ensign with the 1st Foot in 1789.

In 1794, he served as a junior lieutenant-colonel in the Netherlands, commanded by the Duke of York. He also saw service in the Mediterranean and the West Indies. In 1805, at the age of 33 years, Drummond had attained the rank of major-general. In 1807, he married Margaret Russell, daughter of William Russell (1734-1817) of Brancepeth Castle.

He spent three years serving as a regimental chief of staff before being reassigned to Ulster. Late in 1813, Drummond was sent to Upper Canada as lieutenant governor, replacing Francis de Rottenburg, an unpopular officer who was considered over-cautious, nervous about any sort of engagement, and reluctant to send reinforcements to vital areas. Successive lieutenant governors—Rottenburg and his predecessor, Roger Hale Sheaffe—had failed to make an impact in the North American war since the death of the successful Sir Isaac Brock at the Battle of Queenston Heights. Drummond soon proved himself in Brock's mould: aggressive and willing to take chances, in December Drummond launched a surprise attack which led to the capture of Fort Niagara.

But while Brock was capable of using several means to convince the population to follow and (eventually) idolize him, Drummond ruled to a large extent by intimidation. Traitors or those suspected of aiding the Americans in any way could expect no mercy from the Lieutenant-Governor. Executions were relatively commonplace, and performed publicly. While Brock is once reported to have shed tears while watching a traitor executed by firing squad, Drummond displayed no such feelings. Despite these occasional displays of brutal and sudden punishment, Drummond was typically respectful of the citizenry as a whole, recognizing that their help would be essential in driving the Americans out of Canada.

Drummond, like Brock and Henry Procter, was continually hungry for reinforcements from the governor general, Sir George Prevost, who held relatively large numbers of troops in reserve at Quebec, despite the fact that no enemy had even come close to endangering the capital. Despite a constant lack of manpower and war material, Drummond had all but driven the American forces from the Niagara by the close of the 1813-14 winter campaign. In July 1814, responding to a request from the beleaguered Major-General Phineas Riall, Drummond went with his troops from York to Fort George to take command from Riall and drive back Jacob Brown's invading soldiers. On 25 July, he ordered an immediate attack on the American forces, which were already engaging Riall's troops near Chippawa. In this way, a small skirmish exploded into the bloody and inconclusive Battle of Lundy's Lane, which cost each side over 850 casualties and left the British in possession of the road, although it is uncertain whether the British drove the Americans from the field, or the Americans drove off the British and were simply forced to withdraw by a lack of supplies. The latter is likely the case, based upon evidence compiled by Donald Graves, a Canadian historian employed at the Directorate of History, Department of National Defence Canada (Graves, 1997).

At Lundy's Lane, Drummond suffered a serious wound from a shot to the neck during the battle and Riall was captured by American forces. Nonetheless, Drummond insisted that Lundy's Lane was a total victory for the British, and tried to smash Brown's army into the ground by chasing them to Fort Erie. An attempt to storm the fort on 14 August was a total failure, partially due to the unfortunate explosion of the fort's magazine that wiped out an entire arm of the British attack force. The casualties from the one attack numbered over 900, greater than one-third of the besieging British army. Drummond's nephew, Lieutenant Colonel William Drummond, was killed during the attack.

Drummond told Prevost that the defeat was entirely due to the disgraceful conduct of his men. However, some of his senior officers (such as Lieutenant Colonel Drummond and Colonel Hercules Scott of the 103rd Regiment, also killed in the failed storming attempt) criticised him