Aedh (a.k.a. Aodh, Aed, or Whitefoot) lived from 840 to 878 and was King of the Picts and Scots from 877 to 878. The wider picture in Scotland at the time is set out in our Historical Timeline.
Other than his parentage, and the fact that he himself had a family (one son went on to become Constantine II in 900) there is not a lot known about King Aedh.
Aedh's nephew Eochaid (the son of his sister and King Rhun of Strathclyde) coveted the Crown of the Picts and Scots though his claim to it was weak. This was bad news, because Eochaid plotted with his rather shadowy kinsman Giric to bring forward his succession. The result was the murder of Aedh by Giric at Strathallan in 878. According to different sources Aedh was either buried in Aberdeenshire, or in what was by now becoming the traditional final resting place of Scottish Kings, the graveyard at Saint Oran's Chapel on the Isle of Iona.
He was succeeded by the uneasy joint Kingship of Eochaid and Giric.