On 24 July 1837, Rajendra's youngest son, Devendra Bikram Shah, an infant of six months, died suddenly. It was at once rumored that the child had died of poison intended for his mother the Senior Queen Samrajya Laxmi Devi: given at the instigation of Bhimsen Thapa, or someone of his party. On this charge, Mathbar Singh with his family, the court physicians, Ekdev and Eksurya Upadhyay, and his deputy Bhajuman Baidya, with a few more of the nearest relatives of the Thapas were incarcerated, proclaimed outcasts, and their properties confiscated.
Before he was made the Minister and the Commander-In-Chief, he had led to the murder of almost all of his enemies and political adversaries. Having seen the fall of Bhimsen Thapa, he believed that having a personal army would prevent his own downfall; so he founded three regiments dedicated to him and only him. He built army barracks around his house for his personal protection. For this, he used the army like slaves, prompting the British Resident Minister Sir Henry Lawrence to advise him not to do so. However, too over-confident in his power, Mathabar Singh Thapa ignored him. He even claimed that he would be the first prime minister since the time of Prithvi Narayan Shah to die of old age and not out of the conspiracy. In 1845 January 4, he declared himself as the "Prime Minister of Nepal". This was the first time anyone had been titled "Prime Minister" in the history of Nepal. All the others before him were either titled as Mukhtiyar or Mul Kajis. It is believed that at that time he had become even more powerful than the King of Nepal. His power and over-influence in the Nepalese politics and even in the personal life of the monarchy itself led to the eclipse of his power and his downfall by the hands of Jang Bahadur Rana.
When Mathabar Singh Thapa declined the Queen's request to help her make her own son king, the Queen joined those against him and plotted his downfall. But just to appease him, he was provided the title of "Prime Minister" while conspiracy to murder him was going on behind. Finally, when all the preparations for his murder were made, he was called to the Royal Palace at night, informing him incorrectly, that the Queen had been ill from some disease. Though he was warned by his own son, and his mother, he went to the palace. When he was sleeping Jang Bahadur was hiding under his bed. He was shot multiple times on his back from under the bed by Jang Bahadur Rana where he immediately died. The next day King Rajendra declared that he had himself killed Mathabar Singh Thapa accusing him of several activities that he had done to undermine his own (Rajendra's) power.
The murder of Mathabar Singh Thapa led to the political instability in Nepal. Though, Fatte Jung Shah was declared the Prime Minister (1845 September 23), Gagan Singh had more regiments (7) of the army under him and was more powerful. Jung Bahadur Rana also had 3 regiments under him. Fatte Jungh Shah himself had 3 regiments of the army under his control. Also Gagan Singh had the special support of the queen Rajya Laxmi Devi. British Resident Sir Henry Lawrence once mentioned that, "If there is struggle for power, that struggle will be between Gagan Singh and Jung Bahadur." Ultimately, the extreme power of Gagan Singh led to him being assassinated by King Rajendra and Prime Minister Fatte Jungh Shah in 1846 September 14 at 10 P.M.. The assassination of Gagan Singh led to the Kot massacre and ultimately, the rise of Jung Bahadur Rana.
Mathabarsingh Thapa was the first prime minister of Nepal to wear a crown. The 104 year-ruling Rana Dynasty was also related to him.
Also spelled Mathbar, Mathawar, Mathavar,[2][full citation needed] additionally called Matabar Singh Thapa (Nepali: मातवरसिंह थापा).[3]
Mukhtiyar is translated as Chief Authority and was roughly equivalent to a Prime Minister or Head of Government. /wiki/Mukhtiyar
Kandel 2011, p. 10. - Kandel, Devi Prasad (2011), Pre-Rana Administrative System, Chitwan: Siddhababa Offset Press, p. 95
His coronation of Premiership was the first in Nepal thereby making him the First Prime Minister and Commander-in-chief of Nepal as many of his predecessors bore the same position but not the title.
Acharya, Baburam (2000) [2057 B.S.]. Aba Yesto Kailei Nahos. Kathmandu: Sajha Prakashan. /wiki/Kathmandu
JBR, PurushottamShamsher (1990). Shree Teen Haruko Tathya Britanta (in Nepali). Bhotahity, Kathmandu: Vidarthi Pustak Bhandar. ISBN 99933-39-91-1. 99933-39-91-1
JBR, PurushottamShamsher (1990). Shree Teen Haruko Tathya Britanta (in Nepali). Bhotahity, Kathmandu: Vidarthi Pustak Bhandar. ISBN 99933-39-91-1. 99933-39-91-1
Acharya 2012, p. 152. - Acharya, Baburam (2012), Acharya, Shri Krishna (ed.), Janaral Bhimsen Thapa : Yinko Utthan Tatha Pattan (in Nepali), Kathmandu: Education Book House, p. 228, ISBN 9789937241748
Nepal 2007, p. 104. - Nepal, Gyanmani (2007), Nepal ko Mahabharat (in Nepali) (3rd ed.), Kathmandu: Sajha, p. 314, ISBN 9789993325857
Rana 1988, p. 18. - Rana, Rukmani (April–May 1988), "B.H. Hogson as a factor for the fall of Bhimsen Thapa" (PDF), Ancient Nepal (105), Kathmandu: 13–20, retrieved Jan 11, 2013 http://himalaya.socanth.cam.ac.uk/collections/journals/ancientnepal/pdf/ancient_nepal_105_03.pdf
Acharya 2012, pp. 152–153. - Acharya, Baburam (2012), Acharya, Shri Krishna (ed.), Janaral Bhimsen Thapa : Yinko Utthan Tatha Pattan (in Nepali), Kathmandu: Education Book House, p. 228, ISBN 9789937241748
Rana 1988, p. 18. - Rana, Rukmani (April–May 1988), "B.H. Hogson as a factor for the fall of Bhimsen Thapa" (PDF), Ancient Nepal (105), Kathmandu: 13–20, retrieved Jan 11, 2013 http://himalaya.socanth.cam.ac.uk/collections/journals/ancientnepal/pdf/ancient_nepal_105_03.pdf
Acharya 2012, pp. 152–153. - Acharya, Baburam (2012), Acharya, Shri Krishna (ed.), Janaral Bhimsen Thapa : Yinko Utthan Tatha Pattan (in Nepali), Kathmandu: Education Book House, p. 228, ISBN 9789937241748
Acharya 2012, p. 153. - Acharya, Baburam (2012), Acharya, Shri Krishna (ed.), Janaral Bhimsen Thapa : Yinko Utthan Tatha Pattan (in Nepali), Kathmandu: Education Book House, p. 228, ISBN 9789937241748
Nepal 2007, p. 104. - Nepal, Gyanmani (2007), Nepal ko Mahabharat (in Nepali) (3rd ed.), Kathmandu: Sajha, p. 314, ISBN 9789993325857
Acharya 2012, p. 153. - Acharya, Baburam (2012), Acharya, Shri Krishna (ed.), Janaral Bhimsen Thapa : Yinko Utthan Tatha Pattan (in Nepali), Kathmandu: Education Book House, p. 228, ISBN 9789937241748
Rana 1988, p. 19. - Rana, Rukmani (April–May 1988), "B.H. Hogson as a factor for the fall of Bhimsen Thapa" (PDF), Ancient Nepal (105), Kathmandu: 13–20, retrieved Jan 11, 2013 http://himalaya.socanth.cam.ac.uk/collections/journals/ancientnepal/pdf/ancient_nepal_105_03.pdf
Acharya 2012, pp. 153–154. - Acharya, Baburam (2012), Acharya, Shri Krishna (ed.), Janaral Bhimsen Thapa : Yinko Utthan Tatha Pattan (in Nepali), Kathmandu: Education Book House, p. 228, ISBN 9789937241748
Acharya 2012, p. 154. - Acharya, Baburam (2012), Acharya, Shri Krishna (ed.), Janaral Bhimsen Thapa : Yinko Utthan Tatha Pattan (in Nepali), Kathmandu: Education Book House, p. 228, ISBN 9789937241748
Nepal 2007, p. 104. - Nepal, Gyanmani (2007), Nepal ko Mahabharat (in Nepali) (3rd ed.), Kathmandu: Sajha, p. 314, ISBN 9789993325857
Acharya 2012, p. 154. - Acharya, Baburam (2012), Acharya, Shri Krishna (ed.), Janaral Bhimsen Thapa : Yinko Utthan Tatha Pattan (in Nepali), Kathmandu: Education Book House, p. 228, ISBN 9789937241748
Rana 1988, p. 19. - Rana, Rukmani (April–May 1988), "B.H. Hogson as a factor for the fall of Bhimsen Thapa" (PDF), Ancient Nepal (105), Kathmandu: 13–20, retrieved Jan 11, 2013 http://himalaya.socanth.cam.ac.uk/collections/journals/ancientnepal/pdf/ancient_nepal_105_03.pdf
Acharya 2012, p. 154. - Acharya, Baburam (2012), Acharya, Shri Krishna (ed.), Janaral Bhimsen Thapa : Yinko Utthan Tatha Pattan (in Nepali), Kathmandu: Education Book House, p. 228, ISBN 9789937241748
Pradhan 2012, p. 150. - Pradhan, Kumar L. (2012), Thapa Politics in Nepal: With Special Reference to Bhim Sen Thapa, 1806–1839, New Delhi: Concept Publishing Company, p. 278, ISBN 9788180698132 https://books.google.com/books?id=7PP1yElRzIUC&q=the+assassination+of+rana+bahadur+shah
Acharya 2012, p. 156. - Acharya, Baburam (2012), Acharya, Shri Krishna (ed.), Janaral Bhimsen Thapa : Yinko Utthan Tatha Pattan (in Nepali), Kathmandu: Education Book House, p. 228, ISBN 9789937241748
Acharya 2012, p. 158. - Acharya, Baburam (2012), Acharya, Shri Krishna (ed.), Janaral Bhimsen Thapa : Yinko Utthan Tatha Pattan (in Nepali), Kathmandu: Education Book House, p. 228, ISBN 9789937241748
Nepal 2007, p. 105. - Nepal, Gyanmani (2007), Nepal ko Mahabharat (in Nepali) (3rd ed.), Kathmandu: Sajha, p. 314, ISBN 9789993325857
Nepal 2007, p. 105. - Nepal, Gyanmani (2007), Nepal ko Mahabharat (in Nepali) (3rd ed.), Kathmandu: Sajha, p. 314, ISBN 9789993325857
Acharya 2012, p. 159. - Acharya, Baburam (2012), Acharya, Shri Krishna (ed.), Janaral Bhimsen Thapa : Yinko Utthan Tatha Pattan (in Nepali), Kathmandu: Education Book House, p. 228, ISBN 9789937241748
Whelpton 2004, pp. 28–29. - Whelpton, John (2004), "The Political Role of Brian Hodgson", in Waterhouse, David (ed.), Origins of Himalayan Studies: Brian Houghton Hodgson in Nepal and Darjeeling, Royal Asiatic Society Books (1 ed.), Taylor & Francis, p. 320, ISBN 9781134383634 https://books.google.com/books?id=4eR_AgAAQBAJ&q=Origins+of+Himalayan+Studies%3A+Brian+Houghton+Hodgson+in+Nepal+and+Darjeeling+bhimsen+thapa&pg=PA27
Nepal 2007, p. 105. - Nepal, Gyanmani (2007), Nepal ko Mahabharat (in Nepali) (3rd ed.), Kathmandu: Sajha, p. 314, ISBN 9789993325857
Acharya 2012, p. 159. - Acharya, Baburam (2012), Acharya, Shri Krishna (ed.), Janaral Bhimsen Thapa : Yinko Utthan Tatha Pattan (in Nepali), Kathmandu: Education Book House, p. 228, ISBN 9789937241748
Acharya 1971, p. 13. - Acharya, Baburam (1971), "The Fall of Bhimsen Thapa and The Rise of Jang Bahadur Rana" (PDF), Regmi Research Series, 3, Kathmandu: 214–219 http://himalaya.socanth.cam.ac.uk/collections/journals/regmi/pdf/Regmi_03.pdf
Oldfield 1880, p. 310. - Oldfield, Henry Ambrose (1880), Sketches from Nipal, Vol 1, vol. 1, London: W.H. Allan & Co. https://archive.org/details/sketchesfromnipa01oldf
Oldfield 1880, p. 311. - Oldfield, Henry Ambrose (1880), Sketches from Nipal, Vol 1, vol. 1, London: W.H. Allan & Co. https://archive.org/details/sketchesfromnipa01oldf
Nepal 2007, p. 109. - Nepal, Gyanmani (2007), Nepal ko Mahabharat (in Nepali) (3rd ed.), Kathmandu: Sajha, p. 314, ISBN 9789993325857
Acharya 2012, p. 161. - Acharya, Baburam (2012), Acharya, Shri Krishna (ed.), Janaral Bhimsen Thapa : Yinko Utthan Tatha Pattan (in Nepali), Kathmandu: Education Book House, p. 228, ISBN 9789937241748
Pradhan 2012, p. 164. - Pradhan, Kumar L. (2012), Thapa Politics in Nepal: With Special Reference to Bhim Sen Thapa, 1806–1839, New Delhi: Concept Publishing Company, p. 278, ISBN 9788180698132 https://books.google.com/books?id=7PP1yElRzIUC&q=the+assassination+of+rana+bahadur+shah
Pradhan 2012, p. 165. - Pradhan, Kumar L. (2012), Thapa Politics in Nepal: With Special Reference to Bhim Sen Thapa, 1806–1839, New Delhi: Concept Publishing Company, p. 278, ISBN 9788180698132 https://books.google.com/books?id=7PP1yElRzIUC&q=the+assassination+of+rana+bahadur+shah
Oldfield 1880, p. 313. - Oldfield, Henry Ambrose (1880), Sketches from Nipal, Vol 1, vol. 1, London: W.H. Allan & Co. https://archive.org/details/sketchesfromnipa01oldf
Acharya 2012, p. 161. - Acharya, Baburam (2012), Acharya, Shri Krishna (ed.), Janaral Bhimsen Thapa : Yinko Utthan Tatha Pattan (in Nepali), Kathmandu: Education Book House, p. 228, ISBN 9789937241748
Nepal 2007, p. 110. - Nepal, Gyanmani (2007), Nepal ko Mahabharat (in Nepali) (3rd ed.), Kathmandu: Sajha, p. 314, ISBN 9789993325857
Acharya 1971, p. 17. - Acharya, Baburam (1971), "The Fall of Bhimsen Thapa and The Rise of Jang Bahadur Rana" (PDF), Regmi Research Series, 3, Kathmandu: 214–219 http://himalaya.socanth.cam.ac.uk/collections/journals/regmi/pdf/Regmi_03.pdf
Acharya 1971, p. 17. - Acharya, Baburam (1971), "The Fall of Bhimsen Thapa and The Rise of Jang Bahadur Rana" (PDF), Regmi Research Series, 3, Kathmandu: 214–219 http://himalaya.socanth.cam.ac.uk/collections/journals/regmi/pdf/Regmi_03.pdf
Sharma, Balchandra (1976–1977) [2033 B.S]. Nepal ko Aitehasik Rooprekha. Varanasi: Krishna Kumari Devi. p. 295. /wiki/Varanasi
Acharya 1971, p. 17. - Acharya, Baburam (1971), "The Fall of Bhimsen Thapa and The Rise of Jang Bahadur Rana" (PDF), Regmi Research Series, 3, Kathmandu: 214–219 http://himalaya.socanth.cam.ac.uk/collections/journals/regmi/pdf/Regmi_03.pdf
Acharya 1971, p. 17. - Acharya, Baburam (1971), "The Fall of Bhimsen Thapa and The Rise of Jang Bahadur Rana" (PDF), Regmi Research Series, 3, Kathmandu: 214–219 http://himalaya.socanth.cam.ac.uk/collections/journals/regmi/pdf/Regmi_03.pdf
Acharya 1971, p. 17. - Acharya, Baburam (1971), "The Fall of Bhimsen Thapa and The Rise of Jang Bahadur Rana" (PDF), Regmi Research Series, 3, Kathmandu: 214–219 http://himalaya.socanth.cam.ac.uk/collections/journals/regmi/pdf/Regmi_03.pdf
Acharya 1971, p. 17. - Acharya, Baburam (1971), "The Fall of Bhimsen Thapa and The Rise of Jang Bahadur Rana" (PDF), Regmi Research Series, 3, Kathmandu: 214–219 http://himalaya.socanth.cam.ac.uk/collections/journals/regmi/pdf/Regmi_03.pdf
Acharya 1971, p. 17. - Acharya, Baburam (1971), "The Fall of Bhimsen Thapa and The Rise of Jang Bahadur Rana" (PDF), Regmi Research Series, 3, Kathmandu: 214–219 http://himalaya.socanth.cam.ac.uk/collections/journals/regmi/pdf/Regmi_03.pdf
Acharya 1971, p. 17. - Acharya, Baburam (1971), "The Fall of Bhimsen Thapa and The Rise of Jang Bahadur Rana" (PDF), Regmi Research Series, 3, Kathmandu: 214–219 http://himalaya.socanth.cam.ac.uk/collections/journals/regmi/pdf/Regmi_03.pdf
Acharya 1971, p. 18. - Acharya, Baburam (1971), "The Fall of Bhimsen Thapa and The Rise of Jang Bahadur Rana" (PDF), Regmi Research Series, 3, Kathmandu: 214–219 http://himalaya.socanth.cam.ac.uk/collections/journals/regmi/pdf/Regmi_03.pdf
Indo-Nepalese Relations: 1816 to 1877. Delhi: S. Chand and Co. 1968. p. 228. https://books.google.com/books?id=qF1qGlR2ywoC
Acharya, Baburam (2000) [2057 B.S.]. Aba Yesto Kailei Nahos. Kathmandu: Sajha Prakashan. /wiki/Kathmandu
Edwards, Herbert (1873). Life of Sir Henry Lawrence, Part II. London: Smith Elder and Co. p. 470. /wiki/London
Shrestha, Shree Krishna (1996) "Jangabahadura"; Kathmandu
Shaha, R. (1990). 1769-1885. Manohar. ISBN 9788185425030. Retrieved 2017-09-11. 9788185425030
Regmi 1976b, p. 99. - Regmi, Mahesh Chandra (May 1, 1976b), "Jagir lands of Prime Minister Mathbar Singh Thapa and his sons" (PDF), Regmi Research Series, 8 (5), Kathmandu: 99 http://himalaya.socanth.cam.ac.uk/collections/journals/regmi/pdf/Regmi_08.pdf
Regmi 1976b, p. 99. - Regmi, Mahesh Chandra (May 1, 1976b), "Jagir lands of Prime Minister Mathbar Singh Thapa and his sons" (PDF), Regmi Research Series, 8 (5), Kathmandu: 99 http://himalaya.socanth.cam.ac.uk/collections/journals/regmi/pdf/Regmi_08.pdf
Regmi 1976a, pp. 46–49. - Regmi, Mahesh Chandra (March 1, 1976a), "Birta lands of Mathbar Singh Thapa" (PDF), Regmi Research Series, 8 (3), Kathmandu: 46–49 http://himalaya.socanth.cam.ac.uk/collections/journals/regmi/pdf/Regmi_08.pdf
The figure in the journal shows Rs./Aana as used in ancient monetary measurements in Nepal. 1 Aana was equivalent to 1⁄16th of Nepalese Rupee. Similar to Indian Anna.[39] /wiki/Nepalese_Rupee