What is a good thesis statement about William Butler Yeats?

In addition to the political situation in Ireland (as with "The Second Coming") and his complicated personal feelings about Maud Gonne (as with "The Two Trees), William Butler Yeats' poetry and plays were deeply concerned with Irish folklore and mythology. He wrote about many figures of folklore and myth, including fairy lore and legends (as seen in "The Stolen Child"), as well as Irish heroes.

Some of his mythological poems also express a romantic and mystical connection to the Irish landscape. These poems steeped in Irish culture have themes of mysticism, magic and the supernatural, themes quite different from the more down to earth subject matter of war and politics. Yeats was also interested in the occult and in ceremonial magic and mysticism, and became a famous member of the Order of the Golden Dawn. These studies also formed the basis for some of his poetic themes and he applied some of the magical techniques he learned to expanding the scope of his writing.

It may be that Yeats' interest in folklore and mythology was in part what inspired him to pursue studies of pagan religion and magic; the Order of the Golden Dawn emerged in response to the occult revival in Great Britain. On some level it could also be said that Irish folklore and mythology, that is, the deep literary and spiritual legacy of Irish culture, was what inspired Yeats' political activism, and the desire to preserve and valorize uniquely Irish narratives was at the heart of Yeats' political leanings.