The Treaty of Waitangi between Queen Victoria and Māori was signed in 1840, and as a result, the British sovereign became New Zealand's head of state. New Zealand gradually became independent from Britain and the monarchy evolved to become a distinctly New Zealand institution, represented by unique symbols. The person who is the New Zealand monarch is today shared with 15 other countries within the Commonwealth of Nations, all being independent and the monarchy of each legally distinct. As a result, the current monarch is officially titled "Queen of New Zealand" () and, in this capacity, she, her consort, and other members of the royal family undertake various public and private functions across New Zealand and on behalf of the country abroad. However, the Queen is the only member of the royal family with any constitutional role.