Snodgrass had married Janet Wright in 1814, during his time stationed in Portugal, where they began raising a family. Eventually they had six children.
He was Acting Governor of New South Wales for two months from late 1837 to early 1838,[3] between the departure of the outgoing governor Richard Bourke and the arrival of his replacement, George Gipps. While in this role Snodgrass despatched a Sydney mounted police detachment to pursue the Namoi, Weraerai and Kamilaroi people who had killed five stockmen in separate incidents on recently established pastoral runs in the upper Gwydir River area of New South Wales.[4] Tragically this led to the events in January 1838 which became known as the Waterloo Creek massacre (or the Australia Day Massacre). On 26 January 1838, a New South Wales Mounted Police detachment led by Major James Nunn murdered perhaps 40 to 50 men, women and children. (Some historians claim up to 300 people were killed).[5] The group attacked an encampment of Kamilaroi people at a place that came to be called Waterloo Creek, in remote north west New South Wales.[6][7][8][9]
^Ryan, L. (2003), "Waterloo Creek, northern New South Wales, 1838", in Attwood, Bain; Foster, S.G. (eds.), Frontier Conflict : The Australian Experience, Canberra: National Museum of Australia, pp. 33–43, ISBN1876944110
^R. Milliss, Waterloo Creek: the Australia Day massacre of 1838, George Gipps and the British conquest of New South Wales, University of New South Wales Press, 1994 p.2