Kenneth III (a.k.a. Cináed mac Duib) was King of Alba from 997 to 1005. The wider picture in Scotland at the time is set out in our Historical Timeline.
Kenneth was the son of King Duff, and 4th cousin of the man he succeeded, Constantine III. He was the last King of Alba to be appointed under the law of tanistry: in effect a system that involved the extended family in a vote on the succession. This had produced a system in which the crown had alternated between two increasingly distant strands of the House of Alpin, and directly contributed to overwhelming proportion of Kings of Alba who met their end violently.
But it would be hard to describe the end of tanistry as itself a peaceful process. On 25 March 1005 the Battle of Monzievaird, took place just north of Crieff, close to the location of today's Glenturret Distillery. Kenneth II's son, the future Malcolm II defeated King Kenneth III in the battle, killing both Kenneth and his son Giric. Malcolm later arranged the death of Kenneth III's grandson, so ensuring (he thought) that succession would in future rest with his own branch of the family and there was no need for tanistry.
Kenneth III was succeeded by his cousin, Malcolm II after the battle of Battle of Monzievaird.