The American plan to conquer Canada looked straightforward on paper: a four-pronged attack across the northern border. Brigadier General William Hull would strike from Detroit, Major General Stephen Van Rensselaer would cross the Niagara River, another force would take Kingston via Lake Ontario, and Major General Henry Dearborn would march from Lake Champlain to capture Montreal. Every prong failed. Hull surrendered Fort Detroit on August 13, terrified of Britain's Indigenous allies. Dearborn sat idle at Albany. Van Rensselaer, a New York militia general who had never commanded troops in battle, was given his post largely because the governor of New York wanted this political rival out of the way. Van Rensselaer's army at Lewiston numbered roughly 6,700 men, including about 2,484 regulars and over 4,000 militia. Across the narrow, fast-flowing Niagara River, the village of Queenston lay defended by about 450 British regulars and Canadian militia under Captain James Dennis.

The first attempt to cross, on October 11, collapsed in near-farcical fashion. The officer in charge of the boats allegedly rowed away and deserted, taking most of the oars. Foul weather drenched the waiting troops. Brigadier General Alexander Smyth, commanding the regulars at Black Rock, refused to acknowledge that a militia general outranked him and would not coordinate. Van Rensselaer tried again on October 13. The Americans began crossing a few hours before dawn in twelve batteaux, each holding thirty men. Three boats, including the one carrying Lieutenant Colonel John Chrystie, fought the current and turned back. The remaining ten landed on a narrow gravel beach south of Queenston. British guards spotted them and opened fire. In the fierce exchange that followed, Lieutenant Colonel Solomon Van Rensselaer was hit six times - thigh, heel, thighs, and calf - but survived. Captain John E. Wool of the 13th Infantry, also wounded, took command and pulled the survivors back to the landing point.

Before being evacuated, Solomon Van Rensselaer ordered Wool to climb the heights and storm the redan battery positioned two-thirds up the escarpment. Wool's men found a path through the shrubs and trees, crept behind the position, and sent the British artillerymen fleeing. When Brock galloped into Queenston at dawn, the heights were already in American hands. He had been awakened by the distant thunder of artillery at his headquarters in Niagara, ten miles north, and rode hard to the sound of the guns. Rather than wait for reinforcements from Major General Roger Hale Sheaffe at Fort George, Brock assembled soldiers from the 49th Regiment and militia companies at the base of the escarpment and led them straight up the slope. A musket ball hit his wrist. He pressed on. Then came the fatal shot. His aides carried his body to a house diagonally opposite the home of Laura Secord. Lieutenant Colonel John Macdonell led a second charge and was mortally wounded when his horse was shot out from under him. The British fell back to Vrooman's Point.

With the heights in American hands and the British retreating, the battle should have been an American victory. It was not. On the far bank of the Niagara, thousands of New York militia watched the fighting and refused to cross. They cited their constitutional right not to serve on foreign soil. Meanwhile, Sheaffe arrived with reinforcements from Fort George, accompanied by Mohawk warriors led by John Norton. Rather than repeat Brock's frontal assault, Sheaffe led his column on a wide flanking march, approaching the heights from the west. The Mohawk warriors attacked first, their war cries terrifying the American troops still arriving piecemeal on the Canadian shore. Sheaffe's main force struck the disorganized Americans from the flank. Without reinforcement or hope of evacuation, the American forces on the heights surrendered. The British captured roughly 925 prisoners. American casualties totaled approximately 300 killed and wounded.

The British had won decisively, but the cost was enormous. Brock had been the military commander and civil administrator of Upper Canada, a charismatic leader whose aggressive capture of Detroit weeks earlier had earned him the title "Saviour of Upper Canada" and a knighthood he never lived to learn about. His successor, Sheaffe, received a baronetcy for Queenston Heights but lacked Brock's ability to inspire. Sheaffe was later removed from command after losing the Battle of York the following April. A 56-metre column now stands atop Queenston Heights, known as Brock's Monument, built between 1853 and 1856 to replace an earlier monument destroyed in 1840. Brock and Macdonell are interred at its base. Brock University in St. Catharines, the city of Brockville, and Ontario Highway 405 all bear his name. The Canadian patriotic anthem "The Maple Leaf Forever" sings of Queenston Heights and Lundy's Lane, where "our brave fathers, side by side, for freedom, homes, and loved ones dear, firmly stood and nobly died." The general who charged uphill into a musket ball became, in death, the foundational hero of a country that would not exist for another fifty-five years.