During this period his letters and diary show his unwearied efforts to arrive at the best information on all points with regard to Oude.

These will enable the reader to form a just, opinion on the highly-important subject of the annexation of this kingdom to British India.

The statements of Colonel Sleeman bear inward evidence of his great administrative talents, his high and honourable character, and of his unceasing endeavours to promote the best interests of the King of Oude, so that his kingdom might have been preserved to him.

Colonel Sleeman's views were directly opposed to annexation, as his letters clearly show.
His long and arduous career was now, however, fast drawing to a close.

So early as the summer of 1854 it became evident that the health of General Sleeman was breaking up, and in the August of that year he was attacked by alarming illness.