[4] His elder brother Sir Henry John Leeke rose to the rank of admiral in the Royal Navy.
[22][23] While at Cambridge, in 1827 Leeke instituted the Jesus Lane Sunday School in an attempt to improve conditions in the local slums.
His obituary in The Times commended his "charming manner and old-world courtesy", and described him as "a fine old English gentlemen" who excited respect and affection from those who met him.
[27] In 1863, Leeke's eldest daughter Sophia married Thomas Berry Horsfall, MP for Liverpool; she was his third wife, and died in 1867.
[28][29] His daughter Jane married Edward Latham (d. 1883), housemaster of Repton School then vicar of Holy Trinity Church, Matlock Bath.
[14] The history of Lord Seaton's regiment, (the 52nd light infantry) at the battle of Waterloo; together with various incidents connected with that regiment, not only at Waterloo but also at Paris, in the north of France, and for several years afterwards: to which are added many of the author's reminiscences of his military and clerical careers during a period of more than fifty years was published in two volumes in 1866.
[32] Leeke claimed that the 52nd Foot alone, under the command of Sir John Colborne (later Lord Seaton), was responsible for turning the flank of the Imperial Guard in the last stages of the battle, ensuring the victory, stating on the title page of both volumes that: The author claims for Lord Seaton and the 52nd the honour of having defeated, single-handed, without the assistance of the 1st British Guards or any other troops, that portion of the Imperial Guard of France, about 10,000 in number, which advanced to make the last attack on the British position.
[33] Leeke also lamented that Wellington's despatches had unfairly made no mention of Colborne's vital command, and the 52nd's "daring feat".
[34] His memoirs were partly inspired by what he felt to be a "very great injustice [that] has been done to Lord Seaton and the 52nd Light Infantry, which regiment he commanded at Waterloo, by those who have attempted, in subsequent years, to write the history of that great battle", and that he considered "the truth, with regard to what we knew the 52nd had achieved at Waterloo, ought to see the light".