in 1765, chota nagpur was ceded to the british east india company as part of bengal, bihar, and orissa provinces. the raja of singhbhum asked the british resident at midnapore for protection in 1767, but it was not until 1820 that he acknowledged himself as a feudatory of the british. the restless hos broke the agreement soon and took part in a fierce rebellion of 1831-33, called the kol uprising, along with the mundas. the immediate cause of the kol uprising was the oppression of adivsis by non-adivasi "thikadars" (literally meaning contractors) or farmers of rent. the hos and mundas were joined by the kurukh and the houses of many "dikku" (non-adivasis or outsiders) landlords were burnt and a number of people were killed. it compelled the british to recognise the need for a thorough subjugation of the hos. the uprising was suppressed with a good deal of trouble by several hundred british troops. while local troops quelled the uprising, another group under colonel richards entered singhbhum in november 1836. within three months all the ringleaders surrendered. in 1857, the raja of porahat rose in rebellion and a sizeable section of the hos joined in the revolt. troops were sent who put an end to the disturbances by 1859.