Irish literature's roots have been traced to the 7th-9th century. This is a rich and hardy literature starting with descriptions of the brave deeds of kings, saints and other heroes. These were followed by generous veins of religious, historical, genealogical, scientific and other works. The development of prose, poetry and drama raced along with the times. Modern, well-known Irish writers include: William Yeats, James Joyce, Sean Casey, George Bernard Shaw, Oscar Wilde, John Synge and Samuel Beckett.