[1] His books on Colonial Defence and Colonial Opinions (1873), The Defence of Great and Greater Britain (1879), Naval Intelligence and the Protection of Commerce (1881), The Use and the Application of Marine Forces (1883), Imperial Federation: Naval and Military (1887), followed later by other similar works, made him well known among the rising school of Imperialists, and he was elected to parliament in 1886 as Conservative member for Bow and Bromley (1886–1892), and afterwards (1895–1906) for Great Yarmouth.
He became a large landowner, when he inherited the Dromquinna estate with 4,500 acres in the barony of Dunkerron South (County Kerry, Ireland) from his father-in-law Robert Samuel Palmer.
There in the townland of Dromcunnia outside Kenmare he commissioned the architect James Franklin Fuller around 1890 to build Dromquinna House.
[2] John Colomb was a member of the Carlton Club (then Pall Mall, today St James's Street, London).
Colomb married on 1 January 1866, to Emily Anna, daughter of Robert Samuel Palmer (1802–1891), and widow of Charles Augustus Francis Paget (1832–64), Lieutenant of the Royal Navy and grandson of the first Marquess of Anglesey.