Like Buddhist and Christian monasteries elsewhere, the Mongolian monasteries have since the 16th century acquired riches and secular dependents, gradually increasing their wealth and power. By the beginning of the twentieth century, Outer Mongolia had 583 monasteries and temple complexes, which controlled an estimated 20 percent of the country's wealth. Following the Mongolian Revolution of 1921, authorities of the new Mongolian People's Republic entered into a prolonged struggle with the Buddhist faith in general and the monasteries in particular. In 1938 – amid accusations that the church and monasteries were trying to cooperate with the Japanese, who were promoting a pan-Mongol puppet state – this culminated with the remaining monasteries being dissolved, their property seized, and their monks secularized, interned or executed. Those monastic buildings that had not been destroyed were taken over to serve as local government offices or schools. Only the Gandan Monastery, with a community of 100 monks, was kept open in Ulaanbaatar as the country's sole monastery – more for international display than functionality. Following the Mongolian Revolution of 1990 some monasteries were re-opened.