Ranked-choice voting (RCV) was invented in the 1850s in Europe as a proportional representation system to be used in multi-winner elections. In the 1870s, it was adapted to the single-winner (or instant runoff) form by William Ware, an MIT professor.
After trial runs in the 1850s in Denmark, RCV was used regularly in elections beginning in the late 1800s and early 1900s when states in Australia began adopting the method for their legislative elections. Later, the single-winner form was adopted for Australia’s House of Representatives elections in 1918, and the multi-winner form was adopted for Australia’s Senate in 1948. Malta and the Republic of Ireland adopted the multi-winner version for their Parliamentary elections in 1921; Ireland also uses the single-winner form for some elections (such as President).
Around the same time, RCV was adopted in Australia, cities in the United States began adopting RCV in earnest. Ashtabula, Ohio, became the first place in the United States to use RCV in 1915, using it to elect its city council. RCV spread through the rest of Ohio (to Cleveland, Cincinnati, Toledo, and Hamilton), and across the country to places like Boulder, Colorado; Kalamazoo, Michigan; Sacramento, California; and West Hartford, Connecticut. New York City adopted the multi-winner form for their city council and school board elections in 1936, spurring another 11 cities to adopt RCV quickly.
This spate of adoption brought the number of RCV cities to two dozen, which were spread across six states by the early 1940s. However, even as adoption of RCV grew, repeal efforts succeeded in Cleveland, Hamilton, Michigan, and California. In the late 1940s and throughout the 1950s, repeal efforts continued. Politicians displaced by RCV, lack of organization amongst groups benefited by RCV, and a political climate that turned against the parties elected through the proportional representation of RCV led to the repeal of RCV in 23 of the 24 cities where it was used in the U.S. By 1962, Cambridge was the only city left that retained the RCV system it adopted, a form of multi-winner RCV used to elect their nine-member city council and six-member school board. (It is worth noting that these adoptions and subsequent repeals were all the multi-winner proportional system of RCV which guarantees minority representation, not the single-winner, instant runoff version.)
Even after the American repeal efforts, international uses of RCV continued in places like Australia and Malta. New Zealand (1992), Scotland (2007), and Northern Ireland (1970s) also adopted RCV in either the multi-winner or both the multi- and single-winner form. RCV has seen a resurgence in American cities in the last two decades as places like Minneapolis, Minnesota; San Francisco, California; and Takoma Park, Maryland, have adopted both single-winner and multi-winner forms of RCV. The RCVRC held a webinar diving deeper into this topic with Jack Santucci and Chris Hughes. Watch a recording of the webinar here.