Thapas has been involved in politics of Nepal for long time. Thapas were prominent military heads in various princely states in ancient Nepal. Thapas led military and civil administration in the unified Kingdom of Nepal after 1806 AD. Bhimsen Thapa of Bagale Thapa clan rose to prominence after the assassination of King Rana Bahadur Shah of Nepal by King's step-brother in 1805 AD. After the event, an investigation was run by Bharadars (Ministers) which caused massacre of 55 senior officers at Bhandarkhal garden by Thapa Kaji (ministers) group making them as most dominant faction in Nepalese politics.