Task: Question Answering
Input (English): Passage: During the late 12th century, about 100 years after the Norman conquest (1066), the Normans have removed the native ruling class, replacing it with a new monarchy, aristocracy and clerical hierarchy.
Thomas Becket is a Saxon protégé and facilitator to the carousing King Henry II, who transforms into a man who continually invokes the "honour of God". Henry appoints Becket Lord Chancellor to have a close confidant in this position whom he can completely control. Instead, Becket becomes a major thorn in his side in a jurisdictional dispute. Henry finds his duties as king and his stale arranged marriage to be oppressive, and is described as the "perennial adolescent" by the Bishop of London. Henry is more interested in escaping his duties through drunken forays onto the hunting grounds and local brothels. He is increasingly dependent on Becket, a Saxon commoner, who arranges these debaucheries when he is not busy running Henry's court. This foments great resentment on the part of Henry's Norman noblemen, who distrust and envy this Saxon upstart, as well as the queen and Henry's mother, who see Becket as an unnatural and unseemly influence upon the royal personage.
Henry finds himself in continuous conflict with the elderly Archbishop of Canterbury, who opposes the taxation of Church property to support Henry's military campaigns in France ("Bishop, I must hire the Swiss Guards to fight for me – and no one has ever paid them off with principles!"). During one of his campaigns in coastal France, he receives word that the old archbishop has "gone to God's bosom". In a burst of inspiration, Henry exercises his prerogative to pick the next Archbishop and informs an astonished Becket that he is the royal choice. 
Question: What is the full name of the person who Thomas is a thorn in the side of?
Output (English): King Henry II.