larger Union army now commanded by Joseph Hooker at Chancellorsville, Lee divided his force into three parts. On May 2, Jackson launched a surprise attack against the Union right flank, driving the opposing troops back about two miles. That evening, he was accidentally shot by Confederate pickets. He lost his left arm to amputation; weakened by his wounds, he died of pneumonia eight days later. His death proved a severe setback for the Confederacy, affecting not only its military prospects, but also the morale of its army and the general public. After Jackson's death, his military exploits developed a legendary quality, becoming an important element of the ideology of the "Lost Cause". Ancestry Thomas Jonathan Jackson was a great-grandson of John Jackson (1715/1719–1801) and Elizabeth Cummins (also known as Elizabeth Comings and Elizabeth Needles) (1723–1828). John Jackson was an Irish Protestant from Coleraine, County Londonderry, Ireland. While living in London, England, he was convicted of the capital crime of larceny for stealing £170; the judge at the Old Bailey sentenced him to seven years penal transportation. Elizabeth, a strong, blonde woman almost tall, born in London, was also convicted of felony larceny in an unrelated case for stealing 19 pieces of silver, jewelry, and fine lace, and received a similar sentence. They both were transported on the merchant ship Litchfield, which departed London in May 1749 with 150 convicts. John and Elizabeth met on board and were in love by the time the ship arrived at Annapolis, Maryland. Although they were sent to different locations in Maryland for their bond service, the couple married in July 1755. The family migrated west across the Blue Ridge Mountains to settle near Moorefield, Virginia (now West Virginia) in 1758. In 1770, they moved farther west to the Tygart Valley. They began to acquire large parcels of virgin farming land near the present-day town of Buckhannon, including 3,000 acres (12 km2) in Elizabeth's name. John and his two teenage sons were early recruits for the American Revolutionary War, fighting in the Battle of Kings Mountain on October 7, 1780; John finished the war as captain and served as a lieutenant of the Virginia militia after 1787. While the men were in the Army, Elizabeth converted their home to a haven, "Jackson's Fort", for refugees from Indian attacks. John and Elizabeth had eight children. Their second son was Edward Jackson (1759–1828), and Edward's third son