The thousand-year-old glorious tradition of espionage in Bengal is historically well-established. Kautilya's Arthashastra describes in detail a well-organized and effective spy force of the Mauryan Empire in the third century BC. In 1857 after the Sepoy mutiny (which Karl Marx called the first independence struggle of the subcontinent), the Administration of the East India Company in the Indian subcontinent came to an end and the British government assumed direct authority. The history of the origin of the Special Branch of Bangladesh Police is closely related to the history of this Police force of British Regime in the sub continent. The British Empire was determined to form a civilian force alongside the military in the sub continent. Following this, the police force was formed under the Police Act in 1861. After the formation of Police force the authority came to realize the need for a new intelligence wing to control the Swadeshi movement. During that period British officer Major- General Sir William Henry Sleeman took efforts to collect and distribute field level intelligence under the direction of the central British Government to suppress thugs. Based on the report sent earlier, Lord Bentinckt created the "Secret Services" department in 1835 with Sleeman as its head. In 1835, a post of "General Superintendent" was created to collect and distribute information on thugs throughout India from about a dozen police superintendent's offices spread across the country, the first post being held by William Sleeman. Lord Lytton, the Viceroy of British India during his reign (1876-1880) first thought of an Intelligence Branch of the police to keep the British rule protected from domestic adversaries. In gathering information about those who were secretly active against the British rule, Lord Lytton said, “It is by now no means desirable to create an extensive system of secret police but it is certainly important to pay great attention to all sorts of information regarding foreign emissaries’ entrance or unusual political and social phenomena". Lytton's creation of an "Intelligence Branch" of the police included a "Special Intelligence Branch" to collect information by the police in the subcontinent. This was the first attempt by a central government to collect and disseminate intelligence at the field level. After the first independence struggle of the subcontinent against the British in 1857(Sepoy Mutiny) the Great Rebellion, in 1858 the British government undertook extensive administrative reforms. As a result of these reforms, the process of receiving political news under the direct supervision of British officers was subsequently started. The idea of establishing an intelligence agency for the smooth supervision of the state and to suppress anti-British political activities received institutional recognition in the Secretary of State's secret letter No. 11 dated 25 March 1887, which was titled “Collection of Secret and Political Intelligence in India". Soon after the establishment of the Indian National Congress, this letter was sent to the Viceroy. The British officer, Colonel Henderson, through a letter dated 23 July 1887, highlighted the need for a well-organized Special Branch to the Government of India. Viceroy Lord Dufferin wrote a letter on 15 November 1887 AD (Letter No. 170/1887), which can be called the genesis of the Special Branch. Later, on 23 December 1887 AD, a "Central Special Branch" of Police was established in London by the Secretary of State for India Richard Cross under Order No. 31 of the Ministry of Home Affairs of the Government of British India. The Central Special Branch was receiving intelligence from the provincial police units. The British Government allocated Rs 46,800 rupee per year for the operation of the Special Branch. D McCracken, a British officer of the Punjab cadre, was appointed by Lord Dufferin as the Chief or General Superintendent of this Central Special Branch. On the other hand the Criminal Investigation Department (CID) was established in 1906 to investigate specific offenses in provincial governments, as well as to collect criminal intelligence. It was issued under the direction of the report of the Police Commission chaired by Sir Andrew Fraser in 1902; one of which was Intelligence Branch. In 1st September, 1905 the partition of Bengal was announced soon after which the level of various Anti-British revolutionary activities increased considerably. At the same time, the law and order situation was deteriorated due to the rebellious circumstances in protest of the partition of Bengal.