Throughout much of the 1600s through the 1800s, Japan was largely isolated from the West. During this time, the Japanese samurai thrived, along with feudalism and the Buddhist religion. A tradition known as Sangaku (roughly translated: Japanese temple geometry) was born in this era. Japanese people from all social and educational classes would work to solve difficult geometry problems and inscribe the solutions on tablets, then hung the tablets on the roofs of Shinto and Buddhist temples as votive. Many of these problems are heavily focused on circles, an uncommon method in the West in the same time period.