Auckland underwent significant transformations throughout the 20th century, reshaping its urban landscape and demographic makeup. In the early 1900s, the city's growth was largely driven by trams and railway lines, but the end of World War II marked a shift towards car-centric infrastructure. Arterial roads and motorways began to define the city's expansion, particularly with the construction of the Auckland Harbour Bridge in the late 1950s, which opened up the North Shore for suburban development. The southern suburbs also grew, leading to the creation of Manukau City. This motor vehicle-driven urban sprawl became a key feature of Auckland’s growth in the second half of the century.

The mid-1980s brought sweeping changes to Auckland’s economy due to economic deregulation. The city’s importance surged as many companies relocated their headquarters from Wellington to Auckland, solidifying its role as the economic nerve center of New Zealand. The city also became a major gateway for international tourism, with 75% of the country’s visitors passing through Auckland’s airport. By 2015, Auckland’s port handled 31% of New Zealand’s container trade, further emphasizing its commercial significance.

Auckland’s demographic landscape also shifted dramatically following changes to immigration policies in 1986, allowing greater numbers of immigrants from Asia. This influx transformed Auckland into a multicultural metropolis. By 2006, Auckland’s Asian population had risen to 18%, with 36.2% in the central city, marking a stark contrast to the 1961 census when Asians comprised less than 1% of the population. New arrivals from Hong Kong, Taiwan, and Korea introduced distinct cultural flavors to the city, while other immigrants brought mosques, Hindu temples, halal butchers, and diverse ethnic restaurants to Auckland’s suburbs, contributing to its vibrant, multicultural identity.