On 10 October 1307, an assembly confirmed King Charles' rule, but Matthew Csák and some other oligarchs (Ladislaus Kán, Ivan and Henry II Kőszegi) absented themselves from the assembly. In 1308, Pope Clement V sent a legate to the kingdom in order to strengthen King Charles' position. The legate, Cardinal Gentile Portino da Montefiore managed to persuade Matthew to accept King Charles' rule at their meeting in the Pauline Monastery of Kékes (10 November 1308). Although Matthew himself was not present at the following assembly (27 November) in Pest where King Charles' reign was again confirmed, he sent his envoy to attend at the meeting. Shortly afterwards, King Charles appointed Matthew Palatine of the kingdom. However, at the new coronation of King Charles (15 June 1309), he was only represented by one of his followers. In the next year, King Charles appointed him to the office of master of the treasury, which then was the first high-ranking political position during the first regnal years of Charles as the position of palatine was "devaluated".