Ancestry defines the cultural association and ethnic background of an individual going back three generations. Ancestry is a good measure of the total size of cultural groups in Hornsby regardless of where they were born or what language they speak.

Ancestry data, should be combined with data on Birthplace, Language Spoken at Home and Religion for a more complete picture of Hornsby's ethnic characteristics.

Please note that the "Australian Aboriginal" and "Torres Strait Islander" categories in this topic are not directly comparable from 2021 to previous years, due to a change in the wording of the question. In 2021, these options were marked boxes on the question rather than write-in options. The "Aboriginal and Torres Strait Islander Origin" question is still considered a more reliable count for this group, and can be found on the Population summary page.

Please note: Due to changes in ABS rules around perturbation and additivity of data to protect the confidentiality of individuals, counts of ancestry groups and totals derived from them may differ slightly from those published by the ABS. For more information see notes on data confidentiality.