4 ms·
https://en.wikipedia.org/wiki/README https://en.wikipedia.org/wiki/README points out that "README.TXT" was used in 1974 at http://pdp-10.trailing-edge.com/decus
by eesmith 4y ago
https://en.wikipedia.org/wiki/README https://en.wikipedia.org/wiki/README points out that "README.TXT" was used in 1974 at http://pdp-10.trailing-edge.com/decus_20tap3_198111/01/decus/20-0079/readme.txt.html http://pdp-10.trailing-edge.com/decus_20tap3_198111/01/decus..., which predates VAX/VMS by a couple of years.
That was for a DECsystem-10, so still DEC, just a bit earlier.