Unlike his brother Pratap Singh Shah, who ruled Nepal from his father's death in 1775 until 1777 and was a luxury-loving and indulgent king more interested in tantrism; Bahadur spent most of his time learning about diplomacy from the courtiers in Nuwakot.
His primary goal was to establish friendly relations with these nations and later gain their alliance in order to continue the unification of Nepal, whilst also regaining his brother's trust.
Since it was customary for a woman to kill herself in her own husband's pyre as a part of a Hindu tradition called Sati), several of the top-ranking courtiers opposed Rajendra Laxmi's decision to remain as the Regent.
In order to strengthen her own position, she re-invited the previously exiled Bahadur Shah back to Nepal, and purged her rivals with his support.
[6] However, during a military campaign to invade Tanahu, taking advantage of his absence from the capital, Rajendra Laxmi seized power again on 20 June 1779, at which point Bahadur Shah went on self-exile to Bettiah again.
He took a hardline approach to unification offering one of the options to state kings and princes: accept Gorkha sovereignty while continuing to rule themselves or battle to the death.
[7] Bahadur Shah then crushed the Limbuwan rebellion on his eastern front and annexed Sikkim with Damodar Pande and Amar Singh Thapa as his military generals.
After retirement, Bahadur Shah attempted to relocate to China, but his request was declined, so he relocated himself near the Pashupatinath Temple and started living a simple life and practicing religion alongside the saints at the temple, until he was arrested again and imprisoned in February 1797 on several false charges including attempting to kill the king, hold the king in captivity.
Although most historians of Nepal agree that King Rana Bahadur Shah was definitely involved in his assassination, the exact method remains a matter of controversy.