Korean forefathers continued to develop metal casting technique and casted many gracious and excellent bells. The typical one is the Bell of the Pongdok Temple.
It is incomparably excellent in its artistic grace with its delicate form and reliefs on its surface and can be called an implication of the wisdom and talent of the Korean nation with its beautiful sound.
Japan that had been backward in civilization could not imagine to make such a nice bell on its own.
Japanese aggressors frequently invaded Korea during the Koryo times with the foreign invasion as a major policy and stole many Korean bells.
They added writings to more than 10 bells out of all they plundered in Korea and half of them come under the period between 1367 and 1381.
It is a proof that their plunder of the Korean bells went to the extreme at the end of the Koryo times.
The invaders plundered the bells from the Buddhist temples of Korea to have them hung on different temples in Japan.
After all, only a few of the Korean bells, those imbued with the wisdom and talents of the Korean forefathers, remain in Korea proper.