Bose was born in the Subaldaha village of Burdwan, in the province of Bengal. He had his education in Chandannagar, where his father, Vinodebehari Bose, was stationed.He passed degree in medical science as well as Engineering from France and German.
Though interested in revolutionary activities early in his life, he left Bengal to shun the Alipore bomb case (1908). Dehradun he worked as a head clerk at the Forest Research Institute. There, through Amarendra Chatterjee of the Jugantar led by Jatin Mukherjee(Bagha Jatin), he secretly got involved with the revolutionaries of Bengal and, thanks to Jatindra Nath Banerjee alias Niralamba Swami, the earliest political disciple of Sri Aurobindo, he came across eminent revolutionary members of the Arya Samaj in the United Provinces (currently Uttar Pradesh) and the Punjab.
Following the attempt to assassinate Lord Hardinge, Rash Behari was forced to go into hiding. He was hunted by the colonial police due to his active participation in the failed bomb throwing attempt directed at the Governor General and Viceroy Lord Charles Hardinge in Delhi (the bomb was actually thrown by Basanta Kumar Biswas, a disciple of Amarendra Chatterjee). He returned to Dehra Dun by the night train and joined the office the next day as though nothing had happened. Further, he organised a meeting of loyal citizens of Dehradun to condemn the dastardly attack on the Viceroy.
Lord Hardinge, in his My Indian Years, described the whole incident in an interesting way. During the flood relief work in Bengal in 1913, he came in contact with Jatin Mukherjee in whom he "discovered a real leader of men," who "added a new impulse" to Rash Behari’s failing zeal. Thus during World War I he became extensively involved as one of the leading figures of the Ghadar Conspiracy that attempted to trigger a mutiny in India in February 1915. Trusted and tried Ghadrites were sent to several cantonments to infiltrate into the army. The idea of the Jugantar leaders was that with the war raging in Europe most of the soldiers had gone out of India and the rest could be easily won over. The revolution failed and most of the revolutionaries were arrested. But Rash Behari managed to escape British intelligence and reached Japan in 1915.