Robert Stewart, 1st Marquess of Londonderry PC , was a wealthy Irish landowner who became a marquess due to the influence of his eldest son, the diplomat and politician Castlereagh.
Birth and origins
Robert was born on 27 September 1739, at Mount Stewart, as the eldest son of Alexander Stewart and his wife Mary Cowan. His father was an alderman of Londonderry in 1760, and his grandfather, Colonel William Stewart, commanded one of the two companies of Protestant soldiers that Derry admitted into town when Mountjoy was sent there by Tyrconnell before the start of the siege. Robert's mother was a daughter of John Cowan, also an alderman of that same town. His parents married on 30 June 1737 in Dublin. He appears below among his siblings as the second child:
Robert's mother had a half-brother Robert Cowan from her father's first marriage. This half-brother had made a fortune while being Governor of Bombay and had died in London on 21 February 1737, soon after having returned from Bombay. Robert's parents married about 3 months after his death. In his will the Governor bequeathed his estate to his younger brother and then to his half-sister. His younger brother had died in Bombay in 1736. Robert's father Alexander received the money and used it to buy land from the Colville family at Newtownards and Comber in County Down. Robert's fortune was made.
Robert Stewart remarried, on 7 June 1775, taking for his second wife Frances Pratt, daughter of Charles Pratt, 1st Earl Camden. From his second marriage he had 11 more children:
He was elected to the Irish House of Commons in 1771 as member for Down. Between 1775 and 1783 he lived in Bangor with his wife, while his father was living at Mount Stewart. In 1779, worried by the presence of American and French vessels in the Irish sea, he organised the Newtownards Company of 115 men to act as fencibles.
Father's succession
His father died on 2 April 1781 and he inherited his father's properties in counties Londonderry and Down and settled at Mount Stewart, in the grounds of which he completed the Temple of the Winds, which his father had commissioned. When he lost his seat in 1783, he was appointed to the Irish Privy Council.
Lord Londonderry
In 1789 he was created Baron Londonderry in the Peerage of Ireland. The following year he took his son out of Cambridge University and had him run for the seat of County Down in the Parliament in Dublin, which he won. In 1795 he became Viscount Castlereagh. The following year, on 8 August 1796, he was elevated to Earl of Londonderry. His second son at this point also gained a seat in the Dublin Parliament. Robert Stewart and his two sons favoured the Act of Union and fought to have it presented once more after it had been turned down in 1799. As a result of the vote, Robert Stewart obtained a seat in the House of Lords in London, which he never took up. In 1816 he was created Marquess of Londonderry, due to the influence of his son, Lord Castlereagh. This title is again in the Peerage of Ireland. From 1801 until his death he was an Irish representative peer. He achieved the rare feat of rising from a commoner to a marquess.
Death and succession
He died on 6 April 1821 at Mount Stewart, County Down, and was buried at the nearby Newtownards Priory, where his father already had been laid to rest. He was succeeded by his eldest son Robert as the 2nd Marquess of Londonderry.
