This article records tradition as it has been passed down and reported. Its sources are not yet part of the atlas's verified catalogue.
The single transferable vote was not invented once. It was invented independently, within a few years of each other, by people working in different countries who had never coordinated with one another, a genuine case of parallel discovery rather than one idea spreading outward from a single source. In Denmark, the mathematician and politician Carl Andrae devised a proportional counting method in 1856 and had it adopted for elections to the Danish Rigsraad that same year, introducing the specific innovation of numbered ballots, so that a vote's lower preferences could be recorded and counted without requiring voters to return for a second round. In England, the barrister Thomas Hare arrived at a strikingly similar system independently, publishing it in 1857 in a book called The Machinery of Representation, and his formulation became the version that spread through the English speaking world, eventually adopted by the Proportional Representation Society, later renamed the Electoral Reform Society, in 1884. The two systems were not identical. Hare's original quota, the minimum vote share needed to win a seat, set the bar in a way that could leave seats unfilled in some circumstances, a flaw the barrister Henry Droop corrected mathematically in the 1860s with what is now called the Droop quota, the version almost every STV election in use today actually applies. An even earlier partial precursor exists too: in 1819, a schoolmaster named Thomas Wright Hill used a rudimentary quota and vote transfer system to elect a committee for a literary society in Birmingham, decades before either Andrae or Hare took up the problem in earnest. Three names, three countries, and no evidence any of the earlier inventors knew of the others' work before it was already done.