Robert Devereux Essex, 3d earl of 1591-1646, English parliamentary general; son of the 2d earl. James I restored him (1604) to the estates of his father and arranged his marriage (1606) with Frances Howard, daughter of Thomas Howard, earl of Suffolk. The marriage ended in a famous trial when the countess, who had fallen in love with Robert Carr, earl of Somerset, sued for and obtained (1613) an annulment. After 1620, Essex followed a military and naval career, and from 1626 he was associated with the parliamentary opposition to Charles I . He was second in command of the royal army in the first of the Bishops' Wars in Scotland (1639) and was made privy councilor (1641), but Charles could not keep his allegiance thereafter. Essex commanded the parliamentary forces at the battle of Edgehill (1642). In 1643 he took Reading, relieved Gloucester, and took part in the first battle of Newbury. The next year, however, he quarreled bitterly with Sir William Waller and, disobeying orders, pursued the royalists into the southwest. He was cut off in Cornwall and forced to escape with as many of his men as he could by sea. He opposed the formation of the New Model Army and reluctantly relinquished his command in 1645. Bibliography: See biographies by G. B. Harrison (1937, repr. 1973) and V. F. Snow (1970).