Complex sentence: In 1862, his friend, Takechi Hanpeita, organized the Tosa Loyalist Party-Kinnoto (their political slogan was, "Revere the Emperor, Expel the Foreigners") consisting of mostly of about 200 lower samurai who insisted on the reform of the Tosa government.
Split into simpler sentences: In 1862, his friend, Takechi Hanpeita, organized the Tosa Loyalist Party "Kinnoto". It consisted of about 200 samurai, mostly from the lower rank, who insisted on the reform of the Tosa government.