Mahendra Bir Bikram Shah Dev, was the ninth King of Nepal from 13 March 1955 until his death in 1972, which was due to a heart attack, as told in an interview by his personal physician Dr. Mrigendra Raj Pandey. Following the 1960 coup d'état, he established the partyless Panchayat system, which governed the country for 28 years until the introduction of multi-party democracy in 1990. During his reign, Nepal experienced a period of industrial, political and economic change which opened it to the rest of the world for the first time, after the 104-year-long reign of the Rana rulers, who kept the country under an isolationist policy, came to an end in 1951.

Panchayat was a political system in Nepal from 1961 to 1990. It banned political parties and placed all governmental power, including power over the Council of Ministers and Federal Parliament, under the sole authority of the king; this made the country a de facto absolute monarchy.