The speakers did not use a specific name for their language prior to settlement by the First Fleet.The coastal dialect has been referred to as Iyora (also spelt as Iora or Eora), which simply means "people" (or Aboriginal people), while the inland dialect has been referred to as Dharug, a term of unknown origin or meaning.

[9] The traditional territory of the coastal variety ("Iyora/Eyora", or Kuringgai) was estimated by Val Attenbrow (2002) to include "...the Sydney Peninsula (north of Botany Bay, south of Port Jackson, west to Parramatta), as well as the country to the north of Port Jackson, possibly as far as Broken Bay".

[10][1] With a traditional heritage spanning thousands of years, approximately 70 per cent of the Eora people died out during the nineteenth century as a result of the genocidal policies of colonial Australia, smallpox and other viruses, and the destruction of their natural food sources.

[11][12] However, numerous Aboriginal stone tools found in Sydney's far western suburbs gravel sediments were dated to be from 45,000 to 50,000 years BP, which would mean that humans could have been in the region earlier than thought.

[15][16] Dawes was returned to England in December 1791, after disagreements with Governor Phillip on, among other things, the punitive expedition launched following the wounding of the Government gamekeeper,[17] allegedly by Pemulwuy, a Yora man.

The Indigenous population of Sydney gradually started using English more in everyday usage, as well as New South Wales Pidgin.

This, combined with social upheaval, meant that the local Dharug language started to fade from use in the late nineteenth/early twentieth century.

[18] A wordlist of the local Sydney language was published by William Ridley in 1875, and he noted that, at that time, very few fluent speakers were left.