The wars with Champa and the Mongols left Đại Việt exhausted and bankrupt. The Trần family was in turn overthrown by one of its own court officials, Hồ Quý Ly. Hồ Quý Ly forced the last Trần emperor to abdicate and assumed the throne in 1400. He changed the country name to Đại Ngu and moved the capital to Tây Đô, Western Capital, now Thanh Hóa. Thăng Long was renamed Đông Đô, Eastern Capital. Although widely blamed for causing national disunity and losing the country later to the Ming Empire, Hồ Quý Ly's reign actually introduced a lot of progressive, ambitious reforms, including the addition of mathematics to the national examinations, the open critique of Confucian philosophy, the use of paper currency in place of coins, investment in building large warships and cannons, and land reform. He ceded the throne to his son, Hồ Hán Thương, in 1401 and assumed the title Thái Thượng Hoàng, in similar manner to the Trần kings.^[176] The Hồ dynasty was conquered by the Chinese Ming dynasty in 1407.