In modern England and Wales, the position of mayor descends from the feudal lord's bailiff or reeve (see borough). The chief magistrate of London bore the title of portreeve for considerably more than a century after the Norman Conquest. This official was elected by popular choice, a privilege secured from King John. By the beginning of the 12th century, the title of portreeve gave way to that of mayor as the designation of the chief officer of London, followed around 1190 by that of Winchester. Other boroughs adopted the title later. In the 19th century, in the United Kingdom, the Municipal Corporations Act 1882, Section 15, regulated the election of mayors. The mayor was to be a fit person elected annually on 9 November by the council of the borough from among the aldermen or councillors or persons qualified to be such. His term of office was one year, but he was eligible for re-election. He might appoint a deputy to act during illness or absence, and such deputy must be either an alderman or councillor. A mayor who was absent from the borough for more than two months became disqualified and had to vacate his office. A mayor was ex officio a justice of the peace for the borough during his year of office and the following year. He received such remuneration as the council thought reasonable. These provisions have now been repealed.
In medieval Wales, the Laws of Hywel Dda codified the mayor (Latin: maior; Welsh: maer) as a position at the royal courts charged with administering the serfs of the king's lands. To maintain its dependence on and loyalty to the Crown, the position was forbidden to the leaders of the clan groups. A separate mayor, known as the "cow dung mayor" (maer biswail), was charged with overseeing the royal cattle. There were similar offices at the Scottish and Irish courts.
The office of mayor in most modern English and Welsh boroughs and towns did not in the 20th century entail any important administrative duties, and was generally regarded as an honour conferred for local distinction, long service on the Council, or for past services. The mayor was expected to devote much of his (or her) time to civic, ceremonial, and representational functions, and to preside over meetings for the advancement of the public welfare. His or her administrative duties were to act as returning officer at parliamentary elections, and as chairman of the meetings of the council. However, since reforms introduced in 2000, 14 English local authorities have directly elected mayors who combine the 'civic' mayor role with that of Leader of the Council and have significantly greater powers than either. The mayor of a town council is officially known as "town mayor" (although in popular parlance, the word "town" is often dropped). Women mayors are also known as "mayor"; the wife of a mayor is sometimes known as the "mayoress". Mayors are not appointed to District Councils which do not have borough status. Their place is taken by the Chairman of Council, who undertakes exactly the same functions and is, like a mayor, the civic head of the district concerned.
In Scotland the post holders are known as Convenors, Provosts, or Lord Provosts depending on the local authority.
The original Frankish mayors or majordomos were – like the Welsh meiri – lords commanding the king's lands around the Merovingian courts in Austrasia, Burgundy, and Neustria. The mayorship of Paris eventually became hereditary in the Pippinids, who later established the Carolingian dynasty.
In modern France, since the Revolution, a mayor (maire) and a number of mayoral adjuncts (adjoints au maire) are selected by the municipal council from among their number. Most of the administrative work is left in their hands, with the full council meeting comparatively infrequently. The model was copied throughout Europe in Britain's mayors, Italy's sindacos, most of the German states' burgomasters, and Portugal's presidents of the municipal chambers.
In Medieval Italy, the city-states who did not consider themselves independent principalities or dukedoms – particularly those of the Imperial Ghibelline faction – were led by podestàs.
The Greek equivalent of a mayor is the demarch (Greek: δήμαρχος, lit. "archon of the deme").
In Denmark all municipalities are led by a political official called borgmester, "mayor". The mayor of Copenhagen is however called overborgmester "superior mayor". In that city other mayors, borgmestre (plural), are subordinate to him with different undertakings, like ministers to a prime minister. In other municipalities in Denmark there is only a single mayor.
In Norway and Sweden the mayoral title borgermester/borgmästare has now been abolished. Norway abolished it in 1937 as a title of the non-political top manager of (city) municipalities and replaced it with the title rådmann ("alderman" or "magistrate"), which is still in use when referring to the top managers of the municipalities of Norway. The top elected official of the municipalities of Norway, on the other hand, has the title ordfører, which actually means "word-bearer", i.e. "chairman" or "president", an equivalent to the Swedish word ordförande.
In Sweden borgmästare was a title of the senior judge of the courts of the cities, courts which were called rådhusrätt, literally "town hall court", somewhat of an equivalent to an English magistrates' court. These courts were abolished in 1971. Until 1965 these mayor judges on historical grounds also performed administrative functions in the "board of magistrates", in Swedish known collegially as magistrat. Until 1965 there were also municipal mayors (kommunalborgmästare), who had these non-political administrative roles in smaller cities without a magistrates' court or magistrat. This office was an invention of the 20th century as the smaller cities in Sweden during the first half of the 20th century subsequently lost their own courts and magistrates.
In the 16th century in Sweden, king Gustav Vasa considerably centralised government and appointed the mayors directly. In 1693 king Charles XI accepted a compromise after repeated petitions from the Estate of the Burgesses over decades against the royal mayor appointments. The compromise was that the burgesses in a city could normally nominate a mayor under the supervision of the local governor. The nominee was then to be presented to and appointed by the king, but the king could appoint mayors directly in exceptional cases. This was codified in the Instrument of Government of 1720 and on 8 July the same year Riksrådet ("the Council of the Realm") decided, after a petition from the said Estate, that only the city could present nominees, not the king or anyone else. Thus the supervision of the local governor and directly appointed mayors by the king ceased after 1720 (the so-called Age of Liberty). On 16 October 1723, it was decided after a petition that the city should present three nominees, of whom the king (or the Council of the Realm) appointed one. This was kept as a rule from then on in all later regulations and was also kept as a tradition in the § 31) until 1965.
In Finland, there are two mayors, in Tampere and Pirkkala. Usually in Finland the highest executive official is not democratically elected, but is appointed to a public office by the city council, and is called simply kaupunginjohtaja "city manager" or kunnanjohtaja "municipal manager", depending on whether the municipality defines itself as a city. The term pormestari "mayor", from Swedish borgmästare confusingly on historical grounds has referred to the highest official in the registry office and in the city courts (abolished in 1993) as in Sweden, not the city manager. In addition, pormestari is also an honorary title, which may be given for distinguished service in the post of the city manager. The city manager of Helsinki is called ylipormestari, which translates to "Chief Mayor", for historical reasons. Furthermore, the term "city manager" may be seen translated as "mayor".