Back in the old days when travel was mostly by sea, Amakusa was closer to Shimabara than it was to Kumamoto proper. The Facebook page Samurai Legacy has a piece on Amakusa Shiro, a Christian convert who in 1637 led a rebellion against the nascent Tokugawa shogunate, which was duly crushed; he was executed at the age of 17 and his head was displayed on a pike near Nagasaki as a warning to Christians. A statue of his is erected in Amakusa.
Per the Facebook post:
In 1637, the peasants of Shimabara and the Amakusa islands stopped paying. Taxes had been set at a level the land could not produce, collection was brutal, and Christianity had been outlawed in a region full of Christians.
What they did not have was anyone who knew how to fight a war.
They chose a sixteen-year-old named Amakusa Shiro. His father had served a lord who lost everything at Sekigahara, which left the son a masterless nobody — but still, by birth, a samurai. He could have kept his head down and waited for a household to take him in. Men in his position did exactly that.
He took command of about 37,000 farmers instead.
They seized an abandoned castle at Hara and held it for three months against an army of over 120,000 while the shogunate ran out of ideas and eventually borrowed Dutch cannon to shell it from the sea.
He was seventeen when it ended. Japan stayed closed to the outside world for the next 200 years.　‐ William