context: While the existence of these central government departments and the Six Ministries (which had been introduced since the Sui and Tang dynasties) gave a Sinicized image in the Yuan administration, the actual functions of these ministries also reflected how Mongolian priorities and policies reshaped and redirected those institutions. For example, the authority of the Yuan legal system, the Ministry of Justice, did not extend to legal cases involving Mongols and Semuren, who had separate courts of justice. Cases involving members of more than one ethnic group were decided by a mixed board consisting of Chinese and Mongols. Another example was the insignificance of the Ministry of War compared with native Chinese dynasties, as the real military authority in Yuan times resided in the Privy Council.
question:  When had the Eight Ministries existed?