The Eurovision Song Contest 1974 was the 19th edition of the Eurovision Song Contest, held on 6 April 1974 at the Brighton Dome in Brighton, United Kingdom, and presented by Katie Boyle. It was organised by the European Broadcasting Union (EBU) and host broadcaster the British Broadcasting Corporation (BBC), who staged the event after Compagnie Luxembourgeoise de Télédiffusion (CLT), which had won the 1973 contest for Luxembourg, declined hosting responsibilities as it had staged the competition in 1973. The BBC took over as host after Televisión Española (TVE), which had finished second for Spain in 1973, declined the offer when approached, with the EBU ultimately choosing the BBC over bids from the Israel Broadcasting Authority (IBA) and the BBC's commercial rival ITV. This was the fourth time that the BBC had staged the contest after another broadcaster declined – following the 1960, 1963 and 1972 contests – and the fifth time overall including 1968.

Entries representing eighteen countries were submitted for the contest, with Greece making its first appearance. However, France ultimately did not participate as the contest coincided with the death of French president Georges Pompidou, and with a national day of mourning scheduled for the date of the contest the French broadcaster, Office de Radiodiffusion Télévision Française (ORTF), deemed participating in the event to be inappropriate. The voting system used between 1971 and 1973 was scrapped, and was replaced by the system last used in 1970, with ten people in each country awarding one vote to their favourite song.

The winner was Sweden, with the song "Waterloo", composed by Benny Andersson and Björn Ulvaeus, written by Stig Anderson and performed by ABBA. Italy and the Netherlands finishing second and third respectively, followed by a three-way tie for fourth place between Luxembourg, Monaco and the United Kingdom. It was Sweden's first contest win. After previous success within European markets with "Ring Ring", with which ABBA had attempted to represent Sweden in 1973, "Waterloo" gave the group their first global hit, and their Eurovision win was a launching point for ABBA to become one of the world's best-selling music artists. Olivia Newton-John, who represented the United Kingdom at this event, would also go on to achieve worldwide success in the years following the contest.

The 1974 contest was held in Brighton, United Kingdom. It was the fifth time that the United Kingdom had hosted the contest, having previously done so in 1960, 1963, 1968, and 1972. The selected venue was the Dome, completed in 1805 and originally built for the Prince Regent as stables and a riding school for his personal use. Sold by Queen Victoria in 1850, the stables were converted into a concert hall and assembly rooms in 1867, and the riding school into a market for corn merchants in 1868. The concert hall could normally seat up to 2,102 people, but for the contest some seating was removed for the commentator booths and technical equipment, leaving space for an audience of just over 1,000 people.

Among the other venues considered to stage the event by the BBC were the Royal Opera House and Royal Albert Hall in London, the latter of which had previously staged the 1968 contest. Both venues proved to be unavailable however, with the broadcaster then looking outside of the capital for potential venues. The Dome was then ultimately selected, and this choice was announced publicly by the BBC and EBU in July 1973.

The 1973 contest was won by Luxembourg, represented by Compagnie Luxembourgeoise de Télédiffusion (CLT), with the song "Tu te reconnaîtras" performed by Anne-Marie David, which according to Eurovision tradition made CLT the presumptive host of the 1974 contest. The broadcaster had staged the event on three previous occasions, in 1962, 1966, and 1973, each time in Luxembourg City. As CLT had hosted the event the previous year, it declined the opportunity to stage the event for a second consecutive year due to the financial strain such an undertaking would entail. Spain, which had come second in 1973, was also considered as a potential host for the event, however Televisión Española (TVE) also turned down the opportunity to stage the 1974 contest; TVE had previously hosted the event in 1969.

The European Broadcasting Union (EBU) originally asked the British Broadcasting Corporation (BBC), as the participating broadcaster which came third the previous year, not to make an offer at this initial stage in order to determine if other participating broadcasters were willing to stage the event. Of the four previous events held by the BBC three of these had been staged in place of the previous year's winning broadcaster, specifically the 1960, 1963, and 1972 events. Two offers were subsequently made, from the Israel Broadcasting Authority (IBA) and from the BBC's commercial rival ITV. Concerns were raised about the prospect of hosting the event in Israel; they had just joined the contest in 1973 and it was felt some countries would not be prepared to accept an Israeli-held contest. Israel was also some distance geographically from the core of Western European nations which participated in the event at this time, and IBA still lagged behind many European broadcasters from a technological perspective. A successful ITV bid would have effectively barred the BBC from participating, as only one entry from a given country can participate in the event, resulting in the BBC submitting a counter-offer which the EBU accepted on 7 June 1973.

Broadcasters from a total of eighteen countries submitted entries to compete in this edition of the contest, comprising all seventeen countries which had participated in 1973, and Greece, which was making its first appearance in the contest. Turkish broadcaster, the Turkish Radio and Television Corporation (TRT), had also expressed an interest in competing but it had been too late in submitting its request to the EBU and was subsequently informed that, as the scoreboard with space for eighteen countries had already been constructed, its planned entry would not have been possible. Ultimately, however, only seventeen participating entries were performed at the contest, as French broadcaster, Office de Radiodiffusion Télévision Française (ORTF), made the decision to withdraw from the event due to the death of French president Georges Pompidou on 2 April. With the state memorial service and a national day of mourning scheduled to be held on the same day as the contest, it was deemed by ORTF that competing in and broadcasting the contest would be inappropriate. France would have been represented by the song "La Vie à vingt-cinq ans", written by Christine Fontaine and to have been performed by Dani, with Jean-Claude Petit scheduled to conduct the orchestra during the performance.