Prime Minister of Thailand Rajanubhab took over this role. In fact, the office most considered the precursor of that of the prime minister was the ancient office of "Samuha Nayok" (สมุหนายก), which was run by an "Akkhra Maha Senabodi" (อัครมหาเสนาบดี) or "chief minister in charge of civilian affairs". The first Prime Minister of Siam was Phraya Manopakorn Nititada, a judge. The title of the office was changed from "Prime Minister "of Siam"" to "Prime Minister "of Thailand"" in 1945 and then permanently with the renaming of Siam to Thailand in 1949. For most of its existence the office has been occupied by Army leaders;
2014 Thai coup d'état It ordered the judicial branch to operate under its directives. It transferred Police General Adul to an inactive post in the Office of the Prime Minister and replaced him with Police General Watcharapol Prasarnrajkit. Adul was seen as a loyalist of the deposed government. Immediately after the coup was launched, caretaker Prime Minister Niwatthamrong, who did not attend the talks, left his office at the Ministry of Commerce so as to avoid being apprehended by the military. The NCPO ordered him and the cabinet members who were not detained to report to the military that day. It was reported that