[3] They were a wealthy family of Sephardi Jews,[4] and his youngest brother Joseph Barrow Montefiore (1803–1893)[4] was educated in London and lived in the city.
[5] He became a member of the South Australian Association, formed in 1833 by a group consisting of men of varied backgrounds, from philanthropists to merchants, and including Edward Gibbon Wakefield, Robert Gouger, Robert Torrens Sr and George Fife Angas, who wished to create a new British province in southern Australia.
[3] Montefiore and fellow Commissioner Lieutenant-Colonel George Palmer were responsible for fulfilling all of the agents' and other requirements for the "First Fleet of South Australia" in 1836, under the command of Colonel Light.
[3] Four friends of Light – Palmer, Montefiore, Raikes Currie and Alexander Lang Elder, sent a silver bowl to the Mayor and Corporation of the City of Adelaide in 1859 as a gift.
[9][10][3] Montefiore gifted a painted portrait of himself by Barnett Samuel Marks to the National Gallery of South Australia in 1885.