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. "Forty-six years of
incessant labour," observes a writer at this date, "have had their
influence even on his powerful frame: he has received one of those
terrible warnings believed to indicate the approach of paralysis.
With General Sleeman will depart the last hope of any improvement in
the condition of the unhappy country of Oude. Though belonging to the
elder class of Indian officials, he has never been Hindooized. He
fully appreciated the evils of a native throne: he has sternly, and
even haughtily, pointed out to the King the miseries caused by his
incapacity, and has frequently extorted from his fears the mercy
which it was vain to hope from his humanity."

Later in the year. General Sleeman went to the hills, in the hope of
recruiting his wasted health by change of air and scene; but the
expectation proved vain, and he was compelled to take passage for
England. But it was now too late: notwithstanding the best medical
aid, he gradually sank, and, after a long illness, died on his
passage from Calcutta, on the 10th February, 1856, at the age of
sixty-seven.

His Indian career was, indeed, long and honourable his labours most
meritorious. He was one of those superior men which the Indian
service is constantly producing, who have rendered the name of
Englishman respected throughout the vast empire of British India, and
whose memory will endure so long as British power shall remain in the
East.