S.K. BHUYAN: Anglo-Assamese Relations, 1949, p. 556 and 560

Eastern Assam, according to the division of Scott, covered roughly the present districts of Sibsagar, Lakhimpur, a small portion of Darrang, and the Sadiya Frontier Tract. It thus includes three minor tracts of considerable political importance, viz., the territories occupied by the Moamarias, the Khamtis and Singphos; and as they were managed at first from the British station of Sadiya they were generally known as the Sadiya country, and the name ‘Upper Assam’ come to be strictly applied to the intervening districts between Lower Assam and the Sadiya country.
The Matak country or the tract occupied by the Moamarias lay between the Brahmaputra and the Buri-Dihing and extended as far as Sadiya. It ruler was called the Barsenapati, whose independence had been acknowledged by Purnananda Buragohain and survived the Burmese troubles. In May 1826, Matibar Barsenapati entered into an engagement with David Scott in which he promised to furnish 280 paiks to the British Government. He was allowed to dispose of petty criminal cases in his jurisdiction, but was required to send up serious cases to the British courts with the results of his investigation. The district round Sadiya had been in the occupation of the Khamtis since 1794 when they expelled the Ahom governor and established their own chief in his stead. The Khamti chief Chow Salam Sadiyakhowa Gohain undertook to maintain a force of 200 men armed by the British. The Singpho country lay to the east of the Matak and was bounded on the north by the Lohit river and on the south by the patkai range. As we have seen the Singpho chiefs acknowledged their subjection to the British Government and promised to be friendly and peaceful neighbours. The Moamarias returned to their old agricultural pursuits and gave no trouble to the British Government but the Khamtis and the Singphos gradually became impatient of restraint and into their old predatory habits.
Early in 1830 reports were received of hostile preparations among the Singphos and Khamtis aided by their brethren residing beyond the Frontier. Among at the same time another Assamese prince named Gadadhar, disguished as a Khamti priest had been secretly attempting to win over the troops and assassinate the European officers in Upper Assam. He described himself as an agent of the Burmese monarch who, he said, was preparing troops to invade Assam next year. In March 1830 the Khamtis and the Singphos invaded the plains and set out for Sadiya. Captain Neufville, however, succeeded in dispersing them. With regard to the proposed invasion by the Burmese, arrangements were made to repel such an attack; and Raja Gambhir Sing of Manipur was asked to hold his troops in readiness to march across to Sadiya.
A rebellion in a more determined and violent form had meanwhile been organized by Piali Barphukan, son of Badanchandra, with this assistance of some nobles who had been convicted in Gomdhar’s trial but had succeeded in escaping from prison. The Ahom prince who was proposed for elevation to the throne was one Rupchand Konwar. The leaders addressed letters to the chiefs of the Moamarias, Khamtis, Nagas, Daflas, Manipuris, Garos, and Khasias. They seduced the second son and a few disaffected subjects of the Moamaria chief contrary to the latter’s orders. The letter addressed to the Khamti chief was made over to Captain Neufville who instantly arrested the messenger. In the meantime the rebels, lines; but having failed to carry out their project of attacking the guard retreated to Geleki where they were captured by a detachment with some armed levies.