This is a beautiful poem written by Toghon Temur Khan, the last emperor of the Yuan Dynasty from the Altan Tobchi (Mongolian Historical Chronicles). This was a man who had the world under his name and never owned it, who suffered power struggle after power struggle with no one to trust, who never had control over anyone or anything, and who had to see the end the glory of the Great Ghenghis Khan and Kublai Khan come to a close in his own hands. That was his fate. Where there is a beginning, there is always an end. Such being the order of things, someone has to be there at the end, as not everyone has the fortune to be the one at the beginning. The one who is at the finale has to be brave to go on without the glory of the days before.
(From Wikipedia) http://en.wikipedia.org/wiki/Shangdu