 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".Thomas Jonathan Jackson was the great-grandson of John Jackson (1715/1719–1801) and Elizabeth Cummins (also known as Elizabeth Comings and Elizabeth Needles) (1723–1828).