Edward Blayney, 1st Baron Blayney, also Blainey or Blaney (1570-1629) was a Welsh soldier and politician in Ireland. He became Baron Blayney of Monaghan in the Peerage of Ireland. He gave his name to the town of Castleblayney, which he founded in about 1611.
He was born at Gregynog Hall in Tregynon, Montgomeryshire, a younger son of David Lloyd Blayney and his wife Elizabeth Jones. He became a soldier, saw service in Spain and the Low Countries, and came to Ireland in 1598 with Robert Devereux, 2nd Earl of Essex.
After Lord Mountjoy occupied Moyry Pass in 1600 and dismantled the Irish earthworks there, he marched to Mountnorris (halfway between Newry and Armagh) where he built an earthwork fort and left a garrison of 400 men under the command of Blayney, who was then a captain.
In the Parliament of 1613-15 he sat in the Irish House of Commons as MP for Monaghan. He was sworn a member of the Privy Council of Ireland in 1615. In the 1620s he and his eldest son Henry were described as having great influence at the English Court. That he became a very wealthy man is indicated by the fact that he could afford to give his daughter Anne £1200 as her dowry for her ill-fated marriage to Lord Balfour.
As the governor of Monaghan Blayney was granted lands at Ballynalurgan and Muckno on the shore of Lough Muckno. He built Castle Blayney castle, around which the town of Castleblayney has grown, and was created Baron Blayney of Monaghan on 29 July 1621.