Women's suffrage is the right of women to vote in elections. In the beginning of the 18th century, some people sought to change voting laws to allow women to vote. Liberal political parties would go on to grant women the right to vote, increasing the number of those parties' potential constituencies. National and international organizations formed to coordinate efforts towards women voting, especially the International Woman Suffrage Alliance (founded in 1904 in Berlin, Germany).

Many instances occurred in recent centuries where women were selectively given, then stripped of, the right to vote. In Sweden, conditional women's suffrage was in effect during the Age of Liberty (1718–1772).

The first province to continuously allow women to vote was Pitcairn Islands in 1838, and the first sovereign nation was Norway in 1913, as the Kingdom of Hawai'i, which originally had universal suffrage in 1840, rescinded this in 1852 and was subsequently annexed by the United States in 1898. In the years after 1869, a number of provinces held by the British and Russian empires conferred women's suffrage, and some of these became sovereign nations at a later point, like New Zealand, Australia, and Finland. Several states and territories of the United States, such as Wyoming (1869) and Utah (1870), also granted women the right to vote. Women who owned property gained the right to vote in the Isle of Man in 1881, and in 1893, women in the then self-governing British colony of New Zealand were granted the right to vote. In Australia, the colony of South Australia conferred voter rights on all women from 1894, and the right to stand for Parliament from 1895, while the Australian Federal Parliament conferred the right to vote and stand for election in 1902 (although it allowed for the exclusion of "aboriginal natives"). Prior to independence, in the Russian Grand Duchy of Finland, women gained racially-equal suffrage, with both the right to vote and to stand as candidates in 1906. Most major Western powers extended voting rights to women in the interwar period, including Canada (1917), the United Kingdom and Germany (1918), Austria, the Netherlands (1919) and the United States (1920). Notable exceptions in Europe were France, where women could not vote until 1944, Greece (equal voting rights for women did not exist there until 1952, although, since 1930, literate women were able to vote in local elections), and Switzerland (where, since 1971, women could vote at the federal level, and between 1959 and 1990, women got the right to vote at the local canton level). The last European jurisdictions to give women the right to vote were Liechtenstein in 1984 and the Swiss canton of Appenzell Innerrhoden at local level in 1990.

Leslie Hume argues that the First World War changed the popular mood:

The women's contribution to the war effort challenged the notion of women's physical and mental inferiority and made it more difficult to maintain that women were, both by constitution and temperament, unfit to vote. If women could work in munitions factories, it seemed both ungrateful and illogical to deny them a place in the voting booth. But the vote was much more than simply a reward for war work; the point was that women's participation in the war helped to dispel the fears that surrounded women's entry into the public arena.

Pre-WWI opponents of women's suffrage such as the Women's National Anti-Suffrage League cited women's relative inexperience in military affairs. They claimed that since women were the majority of the population, women should vote in local elections, but due to a lack of experience in military affairs, they asserted that it would be dangerous to allow them to vote in national elections.

Extended political campaigns by women and their supporters were necessary to gain legislation or constitutional amendments for women's suffrage. In many countries, limited suffrage for women was granted before universal suffrage for men; for instance, literate women or property owners were granted suffrage before all men received it. The United Nations encouraged women's suffrage in the years following World War II, and the Convention on the Elimination of All Forms of Discrimination Against Women (1979) identifies it as a basic right with 189 countries currently being parties to this convention.