(1133-89) king of England (1154-89). He was the grandson of Henry I, succeeded King Stephen, and was the first Plantagenet king. He reduced the power of the barons and increased the power of the state. He wanted to reduce the power of the Church, which led to his dispute with the Archbishop of Canterbury, Thomas Becket, which ended in Becket's murder. During his rule England established control over Ireland. Henry also introduced various systems of justice which can be seen as the beginning of common law.