Sirimavo Bandaranaike (pictured) was sworn in as prime minister of Ceylon, becoming the world's first democratically elected female head of government.

Sirima Ratwatte Dias Bandaranaike, commonly known as Sirimavo Bandaranaike, was a Sri Lankan politician who became the world's first female prime minister when she was elected Prime Minister of Sri Lanka in 1960. She chaired the Sri Lanka Freedom Party (SLFP) from 1960 to 1994, and served three terms as prime minister from 1960 to 1965, from 1970 to 1977, and from 1994 to 2000 under the presidency of her daughter Chandrika Kumaratunga.

The prime minister of Sri Lanka, officially the prime minister of the Democratic Socialist Republic of Sri Lanka is the most senior member of parliament in the cabinet of ministers. It is the second-most powerful position in Sri Lanka's executive branch behind the president, who is the constitutional chief executive. The Cabinet is collectively held accountable to parliament for their policies and actions. The powers and functions of the prime minister has changed several times since the creation of the office in 1947.

The following is a list of women who have been elected or appointed head of state or government of their respective countries since the interwar period (1918–1939). The first list includes female presidents who are heads of state and may also be heads of government, as well as female heads of government who are not concurrently head of state, such as prime ministers. The list does not include Queens regnant who are heads of state.