Chatusadom or Catustambha (Thai: จตุสดมภ์ RTGS: Chatusadom, literally "Four Pillars" from Sanskrit Catur "Four" + Stambha "Pillars") was the Thai system of central executive governance during the Ayutthaya Kingdom, Thonburi Kingdom and Rattanakosin Kingdom from 1454 to 1892. For about four hundred years, it had served as the constitution of central government of Siam or Thailand until King Chulalongkorn organized Chatusadom into modern ministries and officially established the Cabinet on April 1, 1892.