The High Kings of Ireland were the rulers who held the highest authority over the island during ancient and medieval times. They were not absolute monarchs but rather leaders who gained power through a combination of military strength, political alliances, and recognition from local kings. The title was often contested, leading to conflicts and rivalries among various clans and tribes. The concept of a High King is rooted in Irish mythology and history, with notable figures such as Brian Boru and Niall of the Nine Hostages. The role diminished after the 12th century due to the rise of English influence and the establishment of the Lordship of Ireland.