cal

[damned_colonial]

One of my favourite random unix command line things:

skud@Watson:~$ cal 05 1891
      May 1891
Su Mo Tu We Th Fr Sa
                1  2
 3  4  5  6  7  8  9
10 11 12 13 14 15 16
17 18 19 20 21 22 23
24 25 26 27 28 29 30
31

skud@Watson:~$ cal 04 1891
     April 1891
Su Mo Tu We Th Fr Sa
          1  2  3  4
 5  6  7  8  9 10 11
12 13 14 15 16 17 18
19 20 21 22 23 24 25
26 27 28 29 30

I use this all the time when writing fic in historical fandoms! (It also works for the future, even beyond 2038.)

I've never yet written anything set in September of 1752, but this is interesting:

skud@Watson:~$ cal 09 1752
   September 1752
Su Mo Tu We Th Fr Sa
       1  2 14 15 16
17 18 19 20 21 22 23
24 25 26 27 28 29 30

I'm not sure if it's locale aware, though... 1752 was the British (and colonies) switchover to the Gregorian calendar, but Russia didn't switch til 1918, and Greece til 1923. Anyone know?