oryou (girls und panzer) drawn by nanashiro_gorou

I won't ask any more questions from you

Thus the Edo castle had a bloodless surrender, but dissatisfied with this, the embittered retainers of the Shogunate expanded the resistance in various locations and besieged themselves in Uenokan'eiji. The AkiraYoshi Brigade led by Omura Masujiro of the new government forces defeated them through intense bombardment in the well-known Battle of Ueno where the Shogunate forces were destroyed in their entirety.

Alright, I got it

...and that was a brief overview of the Meiji Period.
In answer to your question,
it was the Anglo-Satsuma War

The likely winner, the Shinsengumi, were divided into two Corps: 24 squads commanded by Hijikata Toshizo from the Shikoku region, and 10 squads of radicals led by Isami Kondo of the Ikedaya region. But at the expected meetup in Ikedaya, Kondo's group attacked with full power without waiting for the main force.

In the 6th year of the Kaei era, 1853 AD, Mathew Perry and the United States Navy East India Fleet landed in Uraga. From that, the Shogunate saw the threat of the Western powers in Asia, and opened up trade, but this collided with and was deemed unacceptable by the Joui ideology.

The Power of a Fan

If only Ryouma was there ...!