Heroes of Xinhai

With the Xinhai Revolution concluded, Mr. Zhang Taiyan's words, 'The revolutionary army prospers, the revolutionary party perishes,' reflected the sentiments of many at the time. The Tongmenghui, considered the only national revolutionary party at the end of the Qing Dynasty, fragmented after the Xinhai Revolution. Why was this? What was the history of the Tongmenghui? What were its contributions? And what were its mistakes?