Newtown probably would have been part of the area lived in by the Cadigal people. Their territory extended from the south side of Port Jackson to around Petersham. It is not known how far south their territory extended. They would have been part of the Eora language group. These groupings did not appear to have strict boundaries, and people often crossed into other territories for ceremonial occasions, or fishing or hunting. Often individuals would have more contact with members of an adjoining group who were close than with members of their own group who were distant. There also seems to have been connections within the members of the different groups who were coastal, and also among those who were inland.

In the first weeks of settlement, Governor Philip estimated the Aboriginal population of the Sydney district as 1500. Other estimates range from 200 to 4000.

Source:
Turbet, Peter The Aborigines of the Sydney District Kangaroo Press, Kenthurst, 1989

References:
Capell, Arthur Aboriginal Languages in the South Central Coast Oceania Vol 41 No 1 1970 p 20-27

Collins, David An Account of the English Colony in New South Wales, with remarks on the dispositions, customs, manners, etc of the native inhabitants of that country A.H. & A.W. Reed, Sydney 1975

Ellis, Jane E. A Troublesome Savage: The story of Pemulwy Canberra 1980

Hunter, John An historical journal of events at Sydney and at sea 1787-1792 Angus and Robertson, Sydney, 1968

Hunter, John An historical journal of the transactions at Port Jackson and Norfolk Island with the discoveries... Libraries Board of Adelaide, Adelaide 1968 [originally John Stockdale, London, 1793]

Sadlier, Richard The Aborigines of Australia Government Press, Sydney 1883

Smith, Keith King Bungaree:... Kangaroo Press, Kenthurst, 1992

Stanbury, P. 10, 000 years of Sydney life University of Sydney, Sydney 1979

Tench, Watkin Sydney's first four years:... Angus and Robertson, Sydney, 1961

Troy, Jakelin The Sydney Language Australian Dictionaries Project, AIATSIS, Canberra, 1994

Troy, Jakelin The Sydney language notebooks and responses to language contact in early colonial NSW Australian Journal of Linguistics Vol 12 No 1 June 1992 p 145-170

Woodroffe, Ronald Pemulwuy - Leader of the Eora tribe and ... Ngoonjook No 9 Novenber 1993 p 23-31