Hồ Nguyên Trừng

Hồ Nguyên Trừng (chữ Hán: 胡元澄; 1374? – 1446?), or Hu Yuancheng in Chinese, was a Vietnamese scholar, official, and engineer in exile in China. He was the oldest son of Hồ Quý Ly (1336–1407) and older brother of Hồ Hán Thương. Under the pen-name Nam Ông (南翁, Old Man of the South), he wrote the Nam Ông mộng lục (Hán tự: 南翁夢錄, literally Dream Memoir of Nam Ông).
Hồ Nguyên Trừng played a role in the Ming-Hồ war where he led the army of Dai Ngu (Hồ dynasty) as well as invented various new types of weapons for Dai Ngu military. He's considered to be an innovator of firearms. His famous inventions including early version of "Eruptor" cannon which later adopted by Ming dynasty and many decked war vessels. After the fall of Hồ dynasty, he was captured by the Ming emperor and forced to teach the Chinese how to cast cannons.