Gilbert Balfour lived from about 1520 to 1576. He served as Sheriff of Orkney and is chiefly remembered for his building of Noltland Castle on Westray and his involvement in two notable murders, of Cardinal Beaton and of Mary Queen of Scots' second husband, Lord Darnley. The wider picture in Scotland at the time is set out in our Historical Timeline.
Gilbert Balfour appears to have been born in Fife in around 1520. On 29 May 1546 he and two of his brothers were members of a group of "Protestant lairds" from Fife who entered St Andrews Castle pretending to be stonemasons. They dragged the unpopular Cardinal David Beaton out of his bedchamber, stabbed him to death, then mutilated him and hung his body from a castle window, in full view of the town of St Andrews. St Andrews Castle then became a gathering place for Protestants from all over the country, including John Knox, who held it in defiance of Marie de Guise's troops. They had hoped for support from Henry VIII of England, but none came. Instead French naval vessels arrived to bombard the castle, which surrendered on 31 July 1547. Many of those captured, including Gilbert Balfour and John Knox, became galley-slaves for the French navy: chained to benches and forced to row.
It is not clear when Balfour was released, though probably, like Knox, in 1549. In 1560 he was granted estates in Orkney by his brother in law, Adam Bothwell, the Bishop of Orkney. During the chaos of the Reformation, large amounts of church land up and down the country found its way into private hands. Gilbert Balfour's slice included the islands of Shapinsay and Westray. Balfour was also appointed to the post of Sheriff of Orkney by Mary Queen of Scots and decided to secure his position by building Noltland Castle on Westray. Balfour was a man whose approach to politics earned him many mortal enemies and Noltland Castle was intended to cover all eventualities, setting what must be a record for the number of gunloops in a castle.
In February 1567 Balfour was implicated in the successful plot to kill Mary Queen of Scots' second husband, Lord Darnley in Edinburgh. Amongst his co-conspirators was James, Earl of Bothwell whose marriage to Mary three months later led directly to her abdication. Balfour's loyalty to Bothwell did not extend to giving him sanctuary when Bothwell turned up on Westray while fleeing to Denmark.
Balfour's support for Mary's claim to the Scottish throne over that of her son, James VI left him increasingly exposed. As a result Balfour had to flee Orkney for Sweden in 1572 and Noltland Castle was taken by Robert Stewart, later to become Earl of Orkney, for James VI. The Balfour family regained possession of the castle in 1574, but Gilbert Balfour remained in Sweden until his habitual plotting led to his execution by the King of Sweden in 1576.