Shimabara Castle main keep

At the beginning of the Edo Period, the Shimabara domain was a low income domain (40,000 koku). Domains with similar income were having quite small castles, with 2 or 3 stories.

However, the lord of Shimabara decided to build a huge castle, with a 5 story main keep, and of course this proved to be too expensive. As a result, heavy taxation was imposed, and this combined with the persecution of Christians led to the Shimabara Rebellion, the strongest uprising that took place during the peaceful Edo Period.