 During Llywelyn's childhood, Gwynedd was ruled by two of his uncles, who split the kingdom between them, following the death of Llywelyn's grandfather, Owain Gwynedd, in 1170.Llywelyn had a strong claim to be the legitimate ruler and began a campaign to win power at an early age.He was sole ruler of Gwynedd by 1200 and made a treaty with King John of England that year.