1. A Church Clock in Cambridge Got a New Tune in 1793
The tune was composed for the clock at Great St Mary's, the University Church in Cambridge, England. The church says it is home to the "original Cambridge Quarters," composed in 1793 and "often misnamed the Westminster Chimes" [1]. A "quarter" here means the little tune a striking clock plays at each quarter of an hour, before it counts out the hour itself.
The sources listed here do not say more about why the church wanted a new tune in 1793. What they do show is that it began as a clock's tune, not a school's bell. It was later copied for Big Ben, doorbells and classrooms.
2. Who Composed the Cambridge Tune Is Still Uncertain
Several sources agree on one point: nobody can say for sure. Joseph Jowett, the university's Regius Professor of Civil Law, was given the job, and he was probably helped by either John Randall, the Professor of Music, or Randall's student William Crotch [2] [3]. The conductor and musicologist Christopher Hogwood, writing to a newspaper, said the variations on the four notes were "said to have been devised" by the young Crotch, and that people in the university once called the tune "Jowett's Jig," after the professor who oversaw the job "without undue haste" [4].
Hogwood also pointed out something practical: the church had only four bells available, and the tune uses exactly four notes. The five different patterns of those four notes, rearranged for each quarter of the hour, are what make the tune feel like it has a beginning, middle and end [4] [2].
3. Did Handel Write the Melody? The Famous Story Has No Support
A popular story says the chime is a variation on four notes from "I Know That My Redeemer Liveth," an aria in George Frideric Handel's oratorio Messiah. Wikipedia describes this as believed "traditionally, though without substantiation" [2], and Hogwood called the link "very tenuous," a coincidence of a four-note shape [4].
Stories that link a familiar tune to a famous composer are easy to repeat, even when the evidence is weak. When the sources cannot show a link, the honest summary is: possible echo, not proven, and not needed to explain the tune.
4. How the Cambridge Tune Became Known as the "Westminster" Chimes
In 1851, Edmund Beckett Denison, an amateur clockmaker who knew the Cambridge chime, picked it for the new clock at the Palace of Westminster, the building in London where the British Parliament meets [2]. That is where "Big Ben" hangs, and the tune's fame spread from there [2]. The name "Westminster Quarters" simply comes from the place that made it famous. Another name for it, "Cambridge Quarters," points to where it came from [2].
A small detail often mixed up: "Big Ben" is properly the name of the great hour bell, not of the tower or the clock. The tower was simply called the Clock Tower until it was renamed Elizabeth Tower in 2012 [3]. The four smaller quarter bells hung around Big Ben play the tune. The notes are G sharp, F sharp, E and B [3].
5. Why the Same Tune Now Rings in Schools, Clocks and Doorbells
The tune is now one of the most commonly used chimes for striking clocks [2]. Classic FM, a UK radio station, lists places where it can be heard: almost any parish church in the UK, the Peace Tower in Ottawa, the San Francisco Ferry Building clock tower, and schools in Japan, China and Taiwan, which often use it to mark the start and end of lessons [3]. Great St Mary's also describes it as imitated by doorbells around the world [1].
None of these sources says why schools chose it. A reasonable guess, and only a guess, is that the tune was already familiar from clocks, and short and easy to recognize. If you ever see a record of a school's actual reason, that would be a good thing to find.
I could not read a source that settles exactly when and by whom this chime first entered Japanese schools, so this article does not name anyone. That part of the story is a good one to look up in a local library.
6. How to Hear and Check the Chime Yourself
Listen for the four notes the next time a school bell, clock or doorbell plays this tune. Try humming it, then hum it backward and see how different it feels.
To dig further, read the church's own page on its bells, which also mentions the Society of Cambridge Youths, who have been ringing the bells there since 1724 [1]. Then compare it with an encyclopedia or news article and notice where they agree and where they say "probably."