18th century, the Nepal Terai was divided into several smaller kingdoms, and the forests were little disturbed. By the 16th century, the rulers of Palpa and Makwanpur controlled the mid-western Terai and extended this control to the eastern Terai by the 17th century. They controlled the area of today's districts of Saptari, Siraha, Dhanusa, Mahottari and Sarlahi. The rulers of Makwanpur controlled the central Terai region of present-day Nepal, and the rulers of Vijayapur controlled today's Sunsari, Morang and Jhapa Districts. The Shah rulers conquered the eastern Nepal Terai in the 1770s. They also conquered land in the eastern Terai that belonged to the Kingdom of Sikkim. The Tulsipur State in the Dang Valley of Nepal's western Terai was also an independent kingdom, until it was conquered in 1785 by Bahadur Shah of Nepal during the unification of Nepal. Since the late 18th century, the Shah rulers encouraged Indian people to settle in the Terai and supported famine-stricken Bihari farmers to convert and cultivate land in the eastern Nepal Terai. From at least 1786 onward, they appointed government officers in the eastern Terai districts of Parsa, Bara, Rautahat, Mahottari, Saptari and Morang to levy taxes, collect revenues, and capture Indian elephants and Indian rhinoceros. At the end of the 18th century, between 200 and 300 elephants were caught annually using snares or nooses. The far-western and mid-western regions of the Nepal Terai called 'Naya Muluk' (new country) lay on the northern periphery of the Awadh dynasty. After Nepal lost the Anglo–Nepalese War in 1816, the British annexed these regions in the Terai when the Sugauli Treaty was ratified. But as reward for Nepal's military aid in the Indian Rebellion of 1857, they returned some of this region in 1860, namely today's districts Kanchanpur, Kailali, Banke and Bardiya. To promote economic development of the Nepal Terai, people from the hills were invited to settle in the region. Since only a few moved to the Terai, Indian people were encouraged to settle. Immigration of Indian people increased between 1846 and 1950. They settled in the eastern Nepal Terai together with native Terai peoples. The Indian Terai remained largely uninhabited until the end of the 19th century, as it was arduous and dangerous to penetrate the dense and marshy malarial jungle. Dacoit gangs retreated to the Terai jungles, and the area was considered lawless and primitive by the British, who sought control of