Trần dynasty
Near the end of the Trần dynasty the technology of gunpowder appeared in the historical records of Đại Việt. It was responsible for the death of the King of Champa, Chế Bồng Nga, after general Trần Khát Chân fired a cannon from his battleship in January 1390. According to the NUS researcher Sun Laichen, the Trần dynasty acquired gunpowder technology from China and effectively used it to change the balance of power between Đại Việt and Champa in favour of Đại Việt. As a result of this Sun reasoned that the need for copper for manufacturing firearms was probably another reason for the order of Hồ Quý Ly to change from copper coins to paper money in 1396. The people of the Trần dynasty and later Hồ dynasty continued to improve their firearms using gunpowder. This resulted in weapons of superior quality to their Chinese counterparts. These were acquired by the Ming dynasty in their invasion of Đại Việt.