The previous electoral redistribution was undertaken in 1875 for the 1875–76 election. In the six years since, New Zealand's European population had increased by 65%. In the 1881 electoral redistribution, the House of Representatives increased the number of European representatives to 91 (up from 84 since the 1875–76 election). The number of Māori electorates was held at four. The House further decided that electorates should not have more than one representative, which led to 35 new electorates being formed, and two electorates that had previously been abolished to be recreated, including Oamaru. This necessitated a major disruption to existing boundaries.
Through an amendment in the Electoral Act in 1965, the number of electorates in the South Island was fixed at 25, an increase of one since the 1962 electoral redistribution. It was accepted that through the more rapid population growth in the North Island, the number of its electorates would continue to increase, and to keep proportionality, three new electorates were allowed for in the 1967 electoral redistribution for the next election. In the North Island, five electorates were newly created and one electorate was reconstituted while three electorates were abolished. In the South Island, three electorates were newly created and one electorate (Oamaru) was reconstituted while three electorates were abolished. The overall effect of the required changes was highly disruptive to existing electorates, with all but three electorates having their boundaries altered. These changes came into effect with the 1969 election.