In 1912, Tagore travelled to Europe and America on tour. His translated writings impressed authors of high caliber such as William Butler Yeats, Ezra Pound, and art critic William Rothenstein. Even more importantly, his English works caught the eyes of the Swiss Academy. In November 1913, Tagore won the Nobel Prize in Literature for his poetry collection entitled Gitanjali. The poems followed the same themes as his long poem "Sun Lion;" they saw the union of two lovers in both a physical, spiritual, and natural sense.