The early settlers of this region seem to be from South East Asia and Indo Aryans from the Gangetic Plains. Many believe that Chinese explorer Zhang Qian discovered a trade route to this region. The north-eastern states were established during the British Raj of the 19 th and early 20 th centuries. After the Indian Independence from the British rule, the North eastern states consisted of Assam, Manipur and Tripura. Subsequently, Nagaland in 1963, Meghalaya in 1972, Arunachal Pradesh in 1975 and Mizoram were formed out of Assam. Sikkim was integrated in 2002.