In Japan, admission will be held in April. but most of countries hold it around in September. This time, we summarize why is admission in April in Japan on this article.
In the early Edo period, children were an important workforce at home and it was not possible for everyone to enroll at the same time because the progress of study was different.  However, the first national university in Japan was established in 1891, and it became desirable to enroll all at once in September, as in the West, but in 1897, the “会計年度” was incorporated into education.  “会計年度” is based on rice cultivation, which is the main industry of Japan, and it ends March and begins April.  By the end of the Meiji era, the government began to actively guide the unification of 会計年度 and school years, and in the Showa era, almost all schools started in April and ended in March.  The season in other countries are as follows.

January…Singapore

February…Australia, Blazil

March…Korea

April…Japan

May…Thailand

June…Philippines

August…Finland

September…America, Canada, England, France, Russia, China etc..

October…Cambodia