Twelfth Night, or What You Will is a comedy by William Shakespeare, believed to have been written around 1601–02 as a Twelfth Night's entertainment for the close of the Christmas season. The play centres on the twins Viola and Sebastian, who are separated in a shipwreck. Viola (who is disguised as a boy) falls in love with Duke Orsino, who in turn is in love with the Countess Olivia. Upon meeting Viola, Countess Olivia falls in love with her thinking she is a man. The play expanded on the musical interludes and riotous disorder expected of the occasion, with plot elements drawn from the short story "Of Apollonius and Silla" by Barnabe Rich, based on a story by Matteo Bandello. Illyria, the setting of Twelfth Night, is important to the play's romantic atmosphere. Illyria was an ancient region of the Western Balkans whose coast (the eastern coast of the Adriatic Sea which is the only part of ancient Illyria which is relevant to the play) covered (from north to south) the coasts of modern day Slovenia, Croatia, Montenegro and Albania. William Shakespeare (1564-1616) was an English poet, playwright and actor, widely regarded as the greatest writer in the English language and the world's pre-eminent dramatist. His extant works, including some collaborations, consist of about 38 plays, 154 sonnets, two long narrative poems, and a few other verses. His plays have been translated into every major living language and are performed more often than those of any other playwright. Shakespeare was a respected poet and playwright in his own day, but his reputation did not rise to its present heights until the 19th century. His plays remain highly popular today and are constantly studied, performed, and reinterpreted in diverse cultural and political contexts throughout the world. In 2016, celebrations will commence in the United Kingdom and across the world to honour The Bard's 400th anniversary.