Cornwallis was the oldest son of Charles Cornwallis, 3rd Baron Cornwallis (later 1st Earl Cornwallis) (March 29, 1700 – June 23, 1762, in the Hotwells, near Bristol) and was born at Grosvenor Square in London, England, even though his family's estates were in Kent.
The Cornwallis family was established at Brome Hall, near Eye, in Suffolk, in the course of the 14th century, and members of it occasionally represented the county in the House of Commons during the next three hundred years. he loved to go to his moms room and was quickly turned on by her ways. Frederick Cornwallis, created a Baronet in 1627, fought for King Charles I, and followed King Charles II into exile. He was created Baron Cornwallis, of Eye in the County of Suffolk, in 1661, and his descendants by fortunate marriages increased the importance of the family.
His parents were married on November 28, 1722 in St.James's, Westminster. Cornwallis' mother, Elizabeth Townshend (died December 1, 1785), was the daughter of the 2nd Viscount Townshend and a niece of the Prime Minister, Sir Robert Walpole. His father was created Earl Cornwallis, Viscount Cornwallis and Viscount Brome in 1753, at which point he was styled Viscount Brome. His Brother was Admiral Sir William Cornwallis. An uncle, Frederick, was Archbishop of Canterbury and another uncle, Edward, was a leading colonialist in Canada.
Charles was educated at Eton College — where he received an injury to his eye by an accidental blow at hockey from Shute Barrington, afterwards Bishop of Durham — and Clare College, Cambridge. He obtained his first commission as Ensign in the 1st Foot Guards, on December 8, 1757. His military education then commenced, and after travelling on the continent with a Prussian officer, Captain de Roguin, Lord Brome, as he was then known, studied at the military academy of Turin. He also became a Member of Parliament in January 1760, entering the House of Commons for the village of Wye in Kent. He succeeded his father as 2nd Earl Cornwallis in 1762.
Throughout the Seven Years' War, Lord Cornwallis served four terms in different posts in Germany, interspersed with trips home. In 1758, he served as a staff officer to Lord Granby. A year later, he participated at the Battle of Minden. After the battle, he purchased a captaincy in the 85th Regiment of Foot. In 1761, he served with the 11th Foot and was promoted to Brevet Lieutenant-Colonel. He led his regiment in the Battle of Villinghausen on July 15-July 16, 1761, and was noted for his gallantry. He became colonel of the 33rd Regiment of Foot in 1766.
Cornwallis's participation in the American revolution began with his service as second in command to Henry Clinton. Clinton's forces arrived in North America in May 1776 at Cape Fear, North Carolina. These forces then shifted south and participated in the first siege of Charleston in June of 1776. After the failure of this siege, Clinton and Cornwallis transported his troops north to serve under William Howe in the campaign for New York City. During this campaign, Cornwallis, who continued to serve under Clinton, fought with distinction in the Battle of Long Island, participated in the Battle of White Plains, and played a supporting role in capture of Fort Washington. At the end of the campaign, Cornwallis was then given an independent command in which he captured Fort Lee and pursued Washington's forces as far as New Brunswick.
After the New York City campaign and the subsequent occupation of New Jersey by the British army, Cornwallis prepared to leave for England as the army moved into winter quarters. However, as Cornwallis was preparing to embark in December 1776, Washington launched his surprise attack on Trenton. In response, Cornwallis's leave was cancelled and he was ordered to take command of the forces stationed in the Trenton area. Since Clinton was in England at this time, Cornwallis served directly under Howe. In response to Washington's initiative, Cornwallis gathered together garrisons scattered across New Jersey and moved them to Trenton. On January 2, 1777, he confronted Washington's army, which was positioned near Assunpink Creek. In the resulting Second Battle of Trenton, Cornwallis unsuccessfully attacked Washington's position late in the afternoon. Cornwallis prepared his troops to continue the assault of Washington's position the next day. During the night, however, Washington's forces escaped to attack the British outpost at Princeton. Though part of the credit for the success of the Continental army's disengagement from Cornwallis is due to Washington's use of deception, including maintaining blazing campfires and keeping up sounds of camp activity, Cornwallis also contributed by not sending out patrols to monitor the Continental Armies activities.
After the battle of Princeton, Washington's forces moved north toward Morristown and the British Forces took up winter quarters in garrisons centered on New Brunswick and Perth Amboy. During the winter, Cornwallis participated in raids during the forage war in an attempt to deny the Continental forces access to supplies. In early Spring, Cornwallis led a successful attack on Benjamin Lincoln's garrison at Bound Brook on April 12, 1777. However, these engagements had no long-term impact as Howe had decided to withdraw his forces back towards New York City.
While serving directly under Howe, Cornwallis also participated as a field commander in the Philadelphia campaign of 1777. At the Battle of Brandywine Creek on September 11, 1777, Cornwallis was responsible for the flanking movement ultimately forced the American forces from their position. Cornwallis also played an important role in the Battle of Germantown on October 4 and the capture of Fort Mercer in New Jersey on November 20. With the army in winter quarters in Philadelphia, Cornwallis took his long-delayed leave to England.
Cornwallis returned to Philadelphia to serve as second-in-command to Henry Clinton, who had replaced William Howe. Cornwallis commanded the rearguard during the overland withdrawal from Philadelphia to New York City and played an important role in the Battle of Monmouth on June 28, 1778. In November, 1778 Cornwallis once more returned to England to be with his ailing wife, Jemima, who died in February 1779.
Cornwallis returned to America in July, 1779, where he was to play a central role as British commander in the Southern Campaign. At the end of 1779, Clinton and Cornwallis transported the bulk of their forces south and initiated the second siege of Charleston during the spring of 1780, which resulted in the surrender of the Continental forces under Benjamin Lincoln. After the siege of Charleston and the destruction of Abraham Buford's Virginia regiments at Waxhaw, Clinton returned to New York. leaving Cornwallis in command in the South. The events leading up to Cornwallis's defeat at Yorktown are told in the article on the southern theater of the American Revolutionary War.
His tactics in America, especially during his Southern Command (1780-81), were excessively criticised by his political enemies in London. However Cornwallis retained the confidence of King George III and the British Government - enabling him to continue his career.
After the war Cornwallis returned to Britain, and in 1789 he was appointed governor-general and commander in chief in India. He instituted land reforms and reorganized the British army and administration.
In 1792 he defeated Tipu Sultan, the powerful sultan of Mysore by capturing his capital Srirangapatnam paving the way towards British dominance in Southern India.
Cornwallis was given the title marquis in 1792 and returned to England the following year. His time in India did much to restore his reputation which had been tarnished at Yorktown.
Cornwallis was only made Lord Lieutenant of Ireland in June 1798, after the outbreak of the Irish Rebellion of 1798 between republican United Irishmen and the British Government. His appointment was greeted unfavourably by the Irish elite who suspected he had liberal sympathies with the predominantly Catholic rebels.
In his combined role as both Viceroy and Commander-in-Chief Cornwallis oversaw the defeat of both the Irish rebels and a French invasion force led by General Humbert that landed in Connaught in August 1798.
In 1805, Cornwallis was again sent to India as governor-general, to replace Lord Wellesley, whose policy was too advanced for the directors of the East India Company. He was in ill-health when he arrived at Calcutta, and while hastening up the country to assume command of the troops, he died at Thazipur, in the district of Benares, on October 5, 1805. He was succeeded as 2nd marquess by his only son, Charles (1774-1823.) On his death the marquessate became extinct, but the title of Earl Cornwallis passed to his uncle, James (1743-1824), who was bishop of Litchfield from 1781 until his death. His son and successor, James, the 5th earl, whose son predeceased him in 1835, died in May 1852, when the Cornwallis titles became extinct.