ADDITIONAL BARRIERS TO INVASION 207

Then below the Sutlaj River, further to the south- east, there was a belt of Mohammedan principalities extending from Delhi to beyond Lucknow, holding all the rich central districts along the Jumna and Ganges, but threatened on the north and west by the Sikhs and Marathas. By far the most considerable of these prin- cipalities was Oudh, whose territory covered the whole northwestern flank of the Company's possessions in Bengal. We have seen that a treaty of alliance was concluded with Oudh by Lord Clive in 1765; and as at the same time he contented the impoverished Moghul emperor by an ample allotment of revenue, the English had nothing to fear from that quarter for the time being. Thus the jealousies and religious animosities of all these states, Hindu and Mohammedan, in North- western India constituted a kind of balance of power, which, in addition to the politic alliances made by Lord Clive, explains the almost entire immunity from dis- turbance on their Bengal frontier enjoyed by the Eng- lish for the next forty years. The year 1765, therefore, when the English thus became firmly settled in Bengal, marks a halting-place in the onward movement of British territorial expan- sion. Lord Clive so far succeeded in his intention, expressed in a letter to the Directors of the Company, written in this same year, " absolutely to bind our pos- sessions and conquests to Bengal," that the English frontiers, as then fixed by him, did not materially advance until the end of the century, when the irrup- tions of the Marathas into the plains of Northern India