Somerset, Edward (d. 1667), earl of Glamorgan and later 2nd marquess of Worcester , envoy to the confederate catholics at Kilkenny, was the eldest son of Henry Somerset, fifth earl and first marquess of Worcester (d. 1646), and his wife, Anne (d. 1639), the daughter of Lord Russell. The Somersets were a catholic family and very wealthy, having sizeable estates in south Wales. Edward spent his early life at Raglan Castle in Monmouthshire, where he was educated privately until he left Britain to travel extensively on a grand tour of Germany, France, and Italy (1619–22). In 1627 he graduated MA from Cambridge University, although he never attended a college there.
When his father inherited the earldom of Worcester in 1628 Somerset became Lord Herbert. Five years later Charles I appointed Herbert to the council of the marches of Wales and made him deputy lord lieutenant of Monmouthshire in 1635. As Charles's kingdom descended into chaos in the early 1640s, Herbert attended upon the king, and his father contributed large sums of money to finance the king's war effort once civil war broke out with parliament. Herbert fortified his estates and garrisoned south Wales for the king, for which support Charles appointed him royalist commander in south Wales in 1643. His forces suffered a disaster outside the town of Gloucester when 2,000 of his men were surprised by the parliamentarians and surrendered. Nevertheless, he retained Charles I's confidence.
Because Herbert had connections with Ireland, his second wife, Margaret O'Brien, being a daughter of Donough O'Brien (qv), 4th earl of Thomond, Charles chose him in 1644 to undertake a secret mission to the confederate catholic government in Kilkenny. In that year he was created earl of Glamorgan, by which title he was known in Ireland. Charles's commission to the earl of 12 March 1645 was given under his signet and signature by the king at Oxford. Glamorgan sailed for Ireland but was shipwrecked off Cumberland; nevertheless by June 1645 he had arrived in Ireland. By August he was in the confederate capital at Kilkenny, where he negotiated a secret agreement which granted extensive religious concessions to the catholics of Ireland in return for 10,000 troops to be sent to the king in England.
Glamorgan's negotiations were highly controversial. Although he was sent to Ireland by the king, Charles himself believed that ‘his honesty or affection to my service will not deceive you; but I will not answer for his judgement’ (Carte MSS 5, ff 7–8). Glamorgan may not have had much confidence in the negotiations, as he drew up a ‘defeasance’ in August 1645 to protect the king's position if the negotiations with the confederates unravelled. He wanted his agreement with the confederates kept secret, which angered the recently arrived papal nuncio, GianBattista Rinuccini (qv). A copy of the agreement fell into parliamentarian hands when the catholic archbishop of Tuam, Malachy O'Queely (qv), was killed by Scottish troops in October 1645 and his papers seized. Rinuccini negotiated a second treaty with Glamorgan which was agreed by December 1645. By February 1646 Glamorgan had collected 6,000 men near Waterford but lacked shipping. That same month Chester, the only English port left in royalist hands suitable for the landing of Irish troops, fell to the parliamentarians. Glamorgan's troops never reached England and were sent to serve in Co. Clare.
Both the royalist lord lieutenant, James Butler (qv), marquess of Ormond, and George Digby, the king's secretary of state, were outraged when they became aware of Glamorgan's negotiations with the confederates. Ormond refused to ratify the agreement and Digby had the earl ‘committed to the castle for high treason’ when Glamorgan visited Dublin. On 20 December 1645 Glamorgan was examined by three lords in Dublin, and in late January 1646 the king issued ‘a disavowal of the proceedings of the earl of Glamorgan in Ireland, so far as they effected religion’ (HMC, 8th report, 62–3). He was soon released from prison and remained in Ireland. On the death of his father in December 1646 he became marquess of Worcester.
In 1647 Worcester negotiated with the Spanish agent in Ireland to send 4,000 soldiers to serve King Philip IV, but nothing came of this venture. In the same year he was appointed general of Munster by the confederate supreme council, although his efforts were stymied by Donough MacCarthy (qv), Viscount Muskerry, who caused a mutiny to break out in Worcester's camp and then took over command of the army himself. Only his lieutenant general, Richard Butler, remained loyal. In 1648 the marquess left Ireland for France, where he went to live near Paris.
In 1649 the parliamentarians confiscated Worcester's estates in Wales, with Oliver Cromwell (qv) himself being a principal beneficiary. When the marquess returned to England in 1652 he was arrested and imprisoned in the Tower of London. However, he was released in 1654 and was given a pension of £3 a week by Cromwell. Upon the restoration of Charles II, Worcester petitioned the king for the return of his estates. In 1665 he wrote to the king that he and his late father had lent £200,000 to Charles I, but left it to his son Henry, Lord Herbert, to rebuild the family fortunes. Worcester now concentrated on his scientific interests, for which he had a passion. He appears to have invented a primitive steam engine, which in 1664 he called ‘his water engine’, and spent the large sum of £50,000 on his experiments, which he undertook at a specially built house at Vauxhall. Although he traded extensively in timber throughout the early 1660s, he remained in debt, in 1666 writing to the king that he ‘dares not even walk the streets for fear of his creditors’ (CSPD, 1665–6, 330).
Worcester died 3 April 1667 and was buried at his ancestral seat at Raglan in Wales. During his life he had married twice. His first wife was Elizabeth Dormer (d. 1635), who was the mother of his son and heir, Henry Somerset, who became 1st duke of Beaufort; the couple also had two daughters. His second wife, Margaret O'Brien, died in 1681. Throughout his life Edward Somerset was a strong supporter of the Stuart kings, and both he and his father expended great sums of money on the royalist cause. His mission to the confederate catholics of Ireland was his greatest undertaking, and his negotiations were successful until King Charles repudiated him.