1939: Nepal's first political party "Nepal Prajaparishad" formed to revolt against Rana dynasty in Nepal by Tanka Prasad Acharya, Dharma Bhakta Mathema, Dashrath Chand, Sukra Raj Shastri, Gangalal Shrestha, Chudaprasad Sharma, Govinda Prasad Upadhya(Poudyal), Puskar Nath Upreti, Mukunda Nath Rimal, Bal Bahadur Pandey, Druba Prasad Dawade, Fadindra Nath Satyal, Hari Krishna Shrestha, Chakra Bahadur Khatri etc.
1940 Oct: Rana governemt arrested almost all members of the PrajaParishad.
1941 Jan 19: Rana governemnt declared death penalty against Dharma Bhakta Mathema, Dashrath Chand, Sukra Raj Shastri and Gangalal Shrestha and jail sentences to many members. And after this PrajaParishad was effectively dissolved.
1946 Jan 25: Nepali National Congress founded by BP Koirala in Cucutta, India.
1948 Aug 4: Nepali Democratic Congress founded by Mahendra Bikram Shah.
1949 Sep 15: Communist Party of Nepal founded in Culcutta, India. This is the party which majority of 10+ present communist parties in Nepal claim origin from.
1950 Apr 9: Nepali congress party founded merging Nepali National Congress and Nepali Democratic Congress parties. Martika Prasad Koirala became first president of the party.
1950 Sep 27/28: Convention of Nepali Congress.
1950 Nov 6: Nepali Congress announced armed revolution in Nepal.
1950 Nov 8: King Tribhuvan took refuse in the Indian Embassy in Kathmandu.
1951 Feb 15: King Tribhuvan returned Nepal.
1951 Feb 18: Rana-Congress government formed. Mohan Shamsher became PM. Other ministers: From Rana side Baber Shamsher JBR (Defence), Chudraj Shamsher (Forests), Nripa Jang Rana (Education), Yagya Bahadur Basnyat (Health) and from congress side: Subarna Shamsher (Finance), B.P. Koirala (Home), Ganesh Man Singh (Commerce and Industry), Bharatmani Sharma (Food and Agriculture) and Bhadrakali Mishra (Transport).
1951 Nov 16: Matrika Prasad Koirala became Prime Minister of Nepal.
1951 Dec 14: Mohan Shumsher, Last Rana PM, went into self-imposed exile in India.
1952 Jan 24: Communist party of Nepal banned after Raksha Dal revolt.
1952 May 26: BP Koirala became second president of the Nepali Congress Party.
1953 Jun 15: Matrika Prasad Koirala became PM for the second time.
1955 Mar 13: King Tribhuvan died. Mahendra became new King of Nepal.
1955 Apr 14: King Mahendra took control of the government.
1956 Jan 27: King appointed Tanka Prasad Acharya as PM.
1956 Apr: Ban lifted on Communist Party of Nepal.
1957 Jul 27: King appointed KI Singh as PM.
1958 May 15: King appointed Nepali congress leader Suberna Shamsher as PM.
1959 Feb 18: First ever democratic election held in Nepal. Nepali Congress became the largest party winning over 2/3 seats (74 among total 109).
1959 May 27: BP Koirala became first elected Prime Minister of Nepal.