Literature

Italian literature's greatest period was in the 14th century. The three most important writers are Dante, Petrarca and Boccaccio. Dante is famous for the Divine Comedy, which is actually about Heaven and Hell! In fact, his description of both Heaven and Hell are very much associated with the modern concept. Petrarca's work is more philosophical, being known as 'the father of humanism'. As a poet, he perfected the sonnet. Boccaccio wrote some timeless works and his 'Decameron' can be enjoyed even by the modern reader.

Macchiavelli is possibly the next most important, but he was a more political than literary writer. His philosophy "the end justifies the means", or "whatever you do, if the outcome is good, then it's ok" changed political thinking from moral to pragmatic, for example in 'The Prince'.
Manzoni is less famous, but just as influential. During the unification of Italy there was a lot of arguing about which dialect to choose as the 'Italian' language. Dante and others had written in Florentine, because he thought it was the most complete and beautiful, as did Manzoni. Manzoni wrote 'I Promessi Sposi' in Florentine and re-wrote it twice more, just to perfect the Italian language (Florentine).
Umberto Eco is the most famous Italian writer alive. He wrote 'In the name of the Rose', which was also made into a movie.

Art

Possibly the best art in the world was produced during the Italian Renaissance art, which went from about 1400 to 1600 and the 'High Renaissance' (the best part of it) from 1450 to 1527. The three most important artists are Michelangelo, Da Vinci and Raphaello. The most famous modern painter is certainly Modigliani.

Myths and Legends

The best known myth in Italy is that of brothers Romulus and Remus, founders of the city of Rome, who were raised by a pack of wolves in a cave not far from modern Rome. However, Italian myths and legends are largely based on Greek stories and culture. The Roman Gods are very similar to the Greek Gods, with Jupiter playing a similar role to the Greek Zeus.