the first branch of the medieval Welsh collection of tales known as The Four Branches of the Mabinogi, Pwyll exchanges places for a year with Arawn, the lord of Annwn (the Otherworld). Despite having his appearance changed to resemble Arawn exactly, Pwyll does not have sexual relations with Arawn's wife during this time, thus establishing a lasting friendship between the two men. This story may, then, provide a background to Gawain's attempts to resist the wife of the Green Knight; thus, the story of Sir Gawain and the Green Knight may be seen as a tale which combines elements of the Celtic beheading game and seduction test stories. Additionally, in both stories a year passes before the completion of the conclusion of the challenge or exchange. Some scholars disagree with this interpretation, however, as Arawn seems to have accepted the notion that Pwyll may reciprocate with his wife, making it less of a "seduction test" per se, as seduction tests typically involve a Lord and Lady conspiring to seduce a knight, seemingly against the wishes of the Lord. After the writing of Sir Gawain and the Green Knight, several similar stories followed. The Greene Knight (15th–17th century) is a rhymed retelling of nearly the same tale. In it, the plot is simplified, motives are more fully explained, and some names are changed. Another story, The Turke and Gowin (15th century), begins with a Turk entering Arthur's court and asking, "Is there any will, as a brother, To give a buffett and take another?" At the end of this poem the Turk, rather than buffeting Gawain back, asks the knight to cut off his head, which Gawain does. The Turk then praises Gawain and showers him with gifts. The Carle of Carlisle (17th century) also resembles Gawain in a scene in which the Carle (Churl), a lord, takes Sir Gawain to a chamber where two swords are hanging and orders Gawain to cut off his head or suffer his own to be cut off. Gawain obliges and strikes, but the Carle rises, laughing and unharmed. Unlike the Gawain poem, no return blow is demanded or given. Themes Temptation and testing At the heart of Sir Gawain and the Green Knight is the test of Gawain's adherence to the code of chivalry. The typical temptation fable of medieval literature presents a series of tribulations assembled as tests or "proofs" of moral virtue.