In 1906, his father Chulalongkorn travelled to Europe to seek treatment for his lung disease, and Chulalongkorn made Vajiravudh Regent of Siam.
En 1906, o rei Chulalongkorn viaxou a Europa para buscar tratamento para a súa enfermidade de pulmón, e nomeou a Vajiravudh rexente do reino.