From the close of the war until the year 1837, Mr. Denison was occupied, like other men of his position, with his duties as a magistrate, the cultivation of his farm, and the rearing of his family. In 1822, he organized the cavalry corps now known as the Governor-General's Body-Guard. When the rebellion broke out, he took up arms again in defence of the Crown, and on the day of the march up Yonge Street, was entrusted with the command of the Old Fort. At about noon a body of men was seen approaching. Eagerly and anxiously the defenders waited, expecting every moment an onset, and determined to meet it like men. The suspense lasted some minutes, when suddenly the Major exclaimed, "Why surely that's my brother Tom!" And so it was. The party consisted of a number of good loyalists, headed by Thomas Denison, of Weston, hastening to the aid of the Government against Mackenzie and his adherents. Of course, the gates were soon thrown open, and, with hearty cheers on both sides, the new-comers entered the Fort.
For six months Major Denison continued in active service with his cavalry, and in the summer of 1838, was promoted to command the battalion of West York Militia. His eldest son, the late Richard L. Denison, succeeded to the command of the cavalry corps, which was kept on service for six months in the winter of 1838-9.
Mr. Denison was elected an alderman of Toronto in the year 1834, and served in the same capacity up to the end of 1843.
That he was quite independent of the "Family Compact," or of any other official clique, is shown by the fact, that on Mackenzie's second expulsion from the House of Assembly in 1832, Alderman Denison voted for his re-election for the County of York.
Our old friend died in 1853, leaving four sons, viz.: Richard L. Denison, of Dover Court, named above; the late George Taylor Denison, of Rusholme; Robert B. Denison, of Bellevue, now Deputy-Adjutant-General for this district; Charles L. Denison, of Brockton: and also one daughter, living. Among his grandchildren are Colonel George T. Denison, commanding the Governor-General's Body Guard, and Police Magistrate; Major F. C. Denison, of the same corps: and Lieutenant John Denison, R. N. The whole number of the Canadian descendants of John Denison, of Hedon, now living, is over one hundred.