Better than the hisotrical account
Historically the 'bad guy' of the film supported the modernization of Japan. I couldn't find anything on him being corrupt. He was warned to leave Edo and said his life didn't matter as he cared more for his country. In fact the Samurai who assassinated him shot him with a Japanese version of a colt through the box of his palanquin. Thank God for movies.
Look up Sakuradamon Incident.