The king seemed firmly seated on his throne--so much so that in 1395 he had found leisure for a long expedition to Ireland, which none of his ancestors had visited since King John. He compelled all the native princes to do him homage, and exercised the royal authority in such a firm manner as had never before been known in the island. But those who looked forward to quiet and prosperous times both for Ireland and for England were destined to be undeceived. In 1397 Richard carried out an extraordinary and unexpected _coup d'état_, which he had evidently premeditated for many years. Having lived down his unpopularity, and made himself many powerful friends, he resolved to take his long-deferred revenge on Gloucester and the other lords appellant. He trumped up a vain story that his uncle was once more conspiring against him, arrested him, and sent him over to Calais, where he was secretly murdered in prison. At the same time Gloucester's two chief confederates of 1387, the earls of Arundel and Warwick, were tried and sentenced to death: the former was actually executed, the latter imprisoned for life. The other two lords appellant, Mowbray, duke of Norfolk,[2] and Henry of Bolingbroke, the son of John of Gaunt, were dealt with a year later. Richard pretended to hold them among his best friends, but in 1398 induced Bolingbroke to accuse Norfolk of treasonable language. Mowbray denied it, and challenged his accuser to a judicial duel. When they were actually facing each other in the lists at Coventry, the king forbade them to fight, and announced that he banished them both--Henry for six years, Norfolk for life. Arbitrary rule of Richard.