Indeed, Bach wrote his in 1722-42
Are you sure this is when Bach wrote them?
Vsevolod P. Zaderatsky (1891-1953). 24 préludes and fugues (written at the Goulag without any instrument)
Watch out! Jmenz has a fugue fetish...
Klarenz Barlow also wrote a set of 13. I'll keep thinking.
A local chap wrote a set recently. I took a few composition lessons from him twenty-five years ago. Our tastes differed too wildly and I didn't understand him, but his knowledge of music is encyclopaedic and he's a brilliant sight reader. https://www.johnwells.co.nz/john-wells-composer.aspx
Excellent. Not just 24 - they're 30! =)