Short answer Do-re-mi comes from the first syllable of each line of an 11th-century Latin chant, and do was originally ut.
The do re mi fa sol la ti you sang in music class. Who came up with these names?
Guido of Arezzo, an Italian music theorist from the 11th century. He's the one who gave each note a name.
He picked a Latin chant dedicated to John the Baptist. Each line of this chant starts one note higher than the line before.
So he used the first syllable of each line as a note name. Ut, Re, Mi, Fa, Sol, La.
Huh? Ut, not do?
UT → DOchanged in Italy in the 1600s
In Italy in the 1600s, ut was changed to do, which ends in a vowel.
The seventh note, ti (or si), was added much later. Guido originally had only six note names.
So we're still singing chant lyrics from a thousand years ago
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