The key figure behind the establishment of universal suffrage in New Zealand is Kate Sheppard. As a prominent suffragist, Sheppard played a crucial role in advocating for women's rights in the late 19th century. Her efforts culminated in the passing of the Representation of the People Act in 1893, which made New Zealand the first self-governing nation to grant women the right to vote in parliamentary elections. Sheppard’s activism and leadership significantly advanced the women's suffrage movement both in New Zealand and globally, inspiring future generations.