The eighth son of a middle class family, Isaac Brock was born in St. Peter Port, Guernsey on October 6, 1769 to John Brock, formerly of the Royal Navy, and Elizabeth de Lisle. Though a strong student, his formal education was brief and included schooling in Southampton and Rotterdam. Appreciative of education and learning, he spent much of his later life working to improve his knowledge. During his early years, Brock also became known as a strong athlete who was particularly gifted at boxer and swimming.
At the age of fifteen, Brock decided to pursue a military career and on March 8, 1785 purchased a commission as an ensign in the 8th Regiment of Foot. Joining his brother in the regiment, he proved a capable soldier and in 1790 was able to purchase a promotion to lieutenant. In this role he worked hard to raise his own company of soldiers and was finally successful a year later. Promoted to captain on January 27, 1791, he received command of the independent company that he had created.
Shortly thereafter, Brock and his men were transferred to the 49th Regiment of Foot. In his early days with the regiment, he earned the respect of his fellow officers when he stood up to another officer who was a bully and prone to challenging others to duels. After a sojourn with the regiment to the Caribbean during which he fell critically ill, Brock returned to Britain in 1793 and was assigned to recruiting duty. Two years later he purchased a commission as a major before rejoining the 49th in 1796. In October 1797, Brock benefited when his superior was compelled to leave the service or face a court-martial. As a result, Brock was able to purchase the lieutenant colonelcy of the regiment at a reduced price.
Fighting in Europe
In 1798, Brock became the effective commander of the regiment with the retirement of Lieutenant Colonel Frederick Keppel. The following year, Brock's command received orders to join Lieutenant General Sir Ralph Abercromby's expedition against the Batavian Republic. Brock first saw combat at the Battle of Krabbendam on September 10, 1799, though the regiment was not heavily engaged in the fighting. A month later, he distinguished himself at the Battle of Egmont-op-Zee while fighting under Major General Sir John Moore.
Advancing over difficult terrain outside of the town, the 49th and British forces were under constant fire from French sharpshooters. In the course of the engagement, Brock was struck in the throat by a spent musket ball but quickly recovered to continue leading his men. Writing of the incident, commented, "I got knocked down shortly after the enemy began to retreat, but never quitted the field, and returned to my duty in less than half an hour." Two years later, Brock and his men embarked aboard Captain Thomas Fremantle's HMS Ganges (74 guns) for operations against the Danes and were present at the Battle of Copenhagen. Originally brought on board for use in assaulting the Danish forts around the city, Brock's men were not needed in the wake of Vice Admiral Lord Horatio Nelson's victory.
Assignment to Canada
With fighting quieting in Europe, the 49th was transferred to Canada in 1802. Arriving, he was initially assigned to Montreal where he was forced to deal with problems of desertion. On one occasion, he violated the American border to recover a group of deserters. Brock's early days in Canada also saw him prevent a mutiny at Fort George. Having received word that members of the garrison intended to imprison their officers before fleeing to the United States, he made an immediate visit to the post and had the ringleaders arrested. Promoted to colonel in October 1805, he took a brief leave to Britain that winter.
Preparing for War
With tensions between the United States and Britain rising, Brock began efforts to improve Canada's defenses. To this end he oversaw improvements to the fortifications at Quebec and improved the Provincial Marine which was responsible for transporting troops and supplies on the Great Lakes. Though appointed brigadier general in 1807 by Governor General Sir James Henry Craig, Brock was frustrated by a lack of supplies and support. This feeling was compounded by a general unhappiness with being posted to Canada when his comrades in Europe were gaining glory by fighting Napoleon.
Wishing to return to Europe, he sent several requests for reassignment. In 1810, Brock was given command of all British force in Upper Canada. The following June saw him promoted to major general and with the departure of Lieutenant Governor Francis Gore that October, he was made the administrator for Upper Canada giving him civil as well as military powers. In this role he worked to alter the militia act to expand his forces and began building relationships with Native American leaders such as the Shawnee chief Tecumseh. Finally granted permission to return to Europe in 1812, he declined as war was looming.
The War of 1812 Begins
With the outbreak of the War of 1812 that June, Brock felt that British military fortunes were bleak. In Upper Canada, he possessed only 1,200 regulars which were supported by around 11,000 militia. As he doubted the loyalty of many Canadians, he believed only around 4,000 of the latter group would be willing to fight. Despite this outlook, Brock quickly sent word to Captain Charles Roberts at St. John Island in Lake Huron to move against nearby Fort Mackinac at his discretion. Roberts succeeded in capturing the American fort which aided in gaining support from the Native Americans.
Triumph at Detroit
Wishing to build on this success, Brock was thwarted by Governor General George Prevost who desired a purely defensive approach. On July 12, an American force led by Major General William Hull moved from Detroit into Canada. Though the Americans quickly withdrew to Detroit, the incursion provided Brock with justification for going on the offensive. Moving with around 300 regulars and 400 militia, Brock reached Amherstburg on August 13 where he was joined by Tecumseh and approximately 600-800 Native Americans.
As British forces had succeeded in capturing Hull's correspondence, Brock was aware that the Americans were short on supplies and scared of attacks by the Native Americans. Despite being badly outnumbered, Brock emplaced artillery on the Canadian side of the Detroit River and began bombarding Fort Detroit. He also employed a variety of tricks to convince Hull that his force was larger than it was, while also parading his Native American allies to induce terror.
On August 15, Brock demanded that Hull surrender. This was initially refused and Brock prepared to lay siege to the fort. Continuing his various ruses, he was surprised the next day when the elderly Hull agreed to turn over the garrison. A stunning victory, the fall of Detroit secured that area of the frontier and saw the British capture a large supply of weapons which were needed for arming the Canadian militia.
Death at Queenston Heights
That fall Brock was forced to race east as an American army under Major General Stephen van Rensselaer threatened to invade across the Niagara River. On October 13, the Americans opened the Battle of Queenston Heights when they began shifting troops across the river. Fighting their way ashore they moved against a British artillery position on the heights. Arriving on the scene, Brock was forced to flee when American troops overran the position.
Sending a message to Major General Roger Hale Sheaffe at Fort George to bring reinforcements, Brock began rallying British troops in the area to retake the heights. Leading forward two companies of the 49th and two companies of York militia, Brock charged up the heights assisted by aide-de-camp Lieutenant Colonel John Macdonell. In the attack, Brock was struck in the chest and killed. Sheaffe later arrived and fought the battle to a victorious conclusion.
In the wake of his death, over 5,000 attended his funeral and his body was buried at Fort George. His remains were later moved in 1824 to a monument in his honor that was constructed on Queenston Heights. Following damage to the monument in 1840, they were shifted to a larger monument on the same site in the 1850s.