Norman times In 1177, the
Normans, who
had conquered great swathes of Ireland, invaded eastern
Ulster and captured territories along its coast.
John de Courcy, who had led the invasion, began building
Dundrum Castle in the early
13th century on top of an earlier fort, "Dun Rury" (Rudraige), which was a seat for the remaining Ulaid tribes east of the
River Bann, after the collapse of the kingdom in the 4th century. The castle was to guard the land routes from
Drogheda to
Downpatrick. In 1203, de Courcy was expelled from Ulster by fellow Norman
Hugh de Lacy, 1st Earl of Ulster. Two years later, de Courcy tried to re-take the castle but failed. It was visited by
King John in 1210, who spent money for minor works to the castle and paid for a garrison there.
15th century Dundrum castle was held by the
Earls of Ulster until the
15th century, it was captured by the
Magennises of Mourne, a Gaelic clan. In 1517, the
Earl of Kildare briefly captured the castle, as did the
Lord Deputy Leonard Grey, 1st Viscount Grane in 1538. The castle was surrendered to the
English Crown in 1601 by Phelim Magennis, granted to Edward Lord Cromwell and sold to the Blundell family. The Magennises re-took the castle during the
Irish Confederate Wars/Eleven Years' War (1641–1653) but lost it to the
Parliamentarians ("Roundheads") of the contenders versus the
Cavaliers of
King Charles I in the simultaneous
English Civil War. The Blundells returned after the civil war during the
Restoration of the Monarchy and built the house on the south edge of the castle.
19th century In 1806,
Arthur Hill, 3rd Marquess of Downshire engaged engineers to develop the area. They recommended deepening the harbour to allow larger vessels to trade. By 1825 they had completed a new pier over long. '' stranded ashore in
Dundrum Bay, 1846 The
SS Great Britain ran aground in Dundrum Bay in 1846. There was no loss of life but it took nearly a year to refloat.
20th century In 1967, nearby
Murlough became
Ireland's first nature reserve. ==Transport==