On this date, April 25, in 1644 the Chongzhen Emperor, last ruler of the Ming Dynasty hung himself from a tree on Meishan in Beiijng, bringing an end to Ming (and thus Han) imperial rule over China. Of course, if you are a Ming restorationist the dynasty may still be the proper rulers of China even today. Regardless of your political stance, his story is a good one, and the link above summarizes it pretty well.