His father's early death in 1460 made a long regency necessary.
His first regent was his mother, Marie of Egmond; when she died three years later, her place was taken by Bishop Kennedy. However, the Bishop lasted only two years and several nobles then tried to control
the country. At this time the English King Edward IV, wanting to have Lancastrian exiles removed from Scotland, went so far as to suggest that the nobles divide Scotland.

However, in 1469, James III gained control of government but was confronted with many problems. He accused his brothers of treason and, when Alexander, Duke of Albany fled to England, Edward IV supported him with the hope of causing even more confusion and trouble in the affairs of Scotland.
Also in 1469, he married Margaret of Denmark and, as a dowry, her father promised money with the Orkney and Shetland Islands as securities. By 1472 it became obvious that the Danish King was unable
to pay and, as a result, the Orkney and Shetland Islands were annexed by Scotland.

Encouraging intellectuals and artists, he alienated himself from the nobles which brought Scotland to the brink of civil war. He imprisoned his own brothers, the Earl of Mar in Craigmillar Castle and the Duke of Albany in Edinburgh Castle. When the Earl of Mar died in prison, James III was accused of killing him. In 1479 the Duke of Albany escaped from Edinburgh Castle by killing his jailers and escaping down the huge rock cliff on a rope. Afterwards, a peace treaty was signed by the two brothers and the Duke of Albany was given back his lands, but again James III forced his brother out of Scotland
and this time it was to be for good.

In 1488 nobles secured the support of the crown prince and, with his knowledge, captured the king at Sauchieburn near Stirling. The crown prince may have approved of the capture of his father but not of
the murder that followed. James III was buried at Cambuskenneth Abbey.

Source: Leo van de Pas