Humans have been living on the continent of Australia (name derived from "Terra Australis"; Latin for "the southern land") for approximately 65,000 years, however population growth was relatively slow until the nineteenth century. Europeans had made some contact with Australia as early as 1606, however there was no significant attempt at settlement until the late eighteenth century. By 1800, the population of Australia was approximately 350,000 people, and the majority of these were Indigenous Australians. As colonization progressed the number of ethnic Europeans increased while the Australian Aboriginal population was decimated through conflict, smallpox and other diseases, with some communities being exterminated completely, such as Aboriginal Tasmanians. Mass migration from Britain and China After the loss of its American colonies in the 1780s, the British Empire looked to other parts of the globe to expand its sphere of influence. In Australia, the first colonies were established in Sydney, Tasmania and Western Australia. Many of these were penal colonies which became home to approximately 164,000 British and Irish convicts who were transported to Australia between 1788 and 1868. As the decades progressed, expansion into the interior intensified, and the entire country was claimed by Britain in 1826. Inland colonization led to further conflict between European settlers and indigenous Australians, which cost the lives of thousands of natives. Inward expansion also saw the discovery of many natural resources, and most notably led to the gold rushes of the 1850s, which attracted substantial numbers of Chinese migrants to Australia. This mass migration from non-European countries eventually led to some restrictive policies being introduced, culminating with the White Australia Policy of 1901, which cemented ethnic-European dominance in Australian politics and society. These policies were not retracted until the second half of the 1900s. Independent Australia Australia changed its status to a British dominion in 1901, and eventually became independent in 1931. Despite this, Australia has remained a part of the British Commonwealth, and Australian forces (ANZAC) fought with the British and their Allies in both World Wars, and were instrumental in campaigns such as Gallipoli in WWI, and the South West Pacific Theater in WWII. The aftermath of both wars had a significant impact on the Australian population, with approximately 90 thousand deaths in both world wars combined, as well as 15 thousand deaths as a result of the Spanish flu pandemic following WWI, although Australia experienced a significant baby boom following the Second World War. In the past fifty years, Australia has promoted immigration from all over the world, and now has one of the strongest economies and highest living standards in the world, with a population that has grown to over 25 million people in 2020.

Life expectancy in Australia was just below 35 in the year 1870, and over the course of the next 150 years, it is expected to have increased to 83.2 by the year 2020. Although life expectancy has generally increased throughout Australia's history, there were several times where the rate deviated from its previous trajectory. the most noticeable changes were between 1890 and 1920. This period included Australia's Independence movement, the implementation of the 'White Australia' policy, the First World War and Spanish Flu epidemic, all of which impacted the demographics of Australia.

This dataset contains an index of census returns of Aboriginal and Torres Strait Island people compiled around 1915.

In 1820, the islands of present-day New Zealand had a population of approximately 100,000 people. This figure would fall until the early 1840s, partly as a result of European diseases brought by colonizers, and a series of destructive inter-tribal wars among the Māori peoples. These conflicts were named the Musket Wars due to the European weapons whose introduction instigated the conflicts, and the wars saw the deaths of between 20,000 and 40,000 Māori, from 1807 to 1837. After falling to just 82 thousand in the 1840s, the population would begin to rise again in 1841 following the establishment of New Zealand as an official British colony, with a strong promotion of European settlement by British citizens sponsored by the Church of England. European migration to New Zealand was low in these early decades, but increased in the mid-19th century, particularly following the discovery of gold in New Zealand’s South Island in the 1860s. This growth would continue throughout the 1870s, in part the result of a strong promotion of mass migration from Britain by Premier Julius Vogel’s administration.

Early 20th century However, between 1881 and the 1920s, the New Zealand government heavily restricted Asiatic migration to the islands, resulting in a fall of population growth rate, which would remain until the Second World War. The country would experience a dip in population during the First World War, in which New Zealand would suffer approximately 18,000 military fatalities, and another 9,000 lost to the coinciding Spanish Flu epidemic. The population would stagnate again in the Second World War, which resulted in the death of almost 12,000 New Zealanders. In the years following the war, New Zealand would see a significant increase in population due to the mixture of a baby boom and a migrant spike from Europe and Asia, following a large demand for unskilled labor. Recent decades This increase continued for several decades, until international factors, such as the oil crises of 1973 and 1979, and the UK's accession to the European Economic Communities (which ended most of New Zealand's trade agreements with Britain; it's largest trade partner), greatly weakened New Zealand's economy in the 1970s. As a result, population growth stagnated during the 1970s, while economic problems persisted into the early 2000s. In contrast, the Great Recession of 2008 did not impact New Zealand as severely as most other developed nations, which allowed the economy to emerge as one of the fastest growing in the world, also leading to dropped unemployment levels and increased living standards. In 2020, with a population of almost five million people, New Zealand is regarded as one of the top countries in the world in terms of human development, quality of life and social freedoms.