K-HB has a nice answer, but I will answer here with some historical data for Germany anyway, because of the relatively good accessibility of sources. I will mainly quote from the paper "Vossische Zeitung", which is available in scanned form from the Staatsbibliothek Berlin here.
In the June 15th, 1893 election, results of all but one constituency were known by Monday, June 19th. The election results from Berlin were already known the morning after the election.
The preliminary(?) official result for the June 16th, 1898 election, were made known before noon on Monday, June 20th. I.e. getting the result took roughly as long as in 1893.
For the 1903 election, there are unfortunately no useful scans in the Staatsbibliothek digital archive.
The results for the 1907*, 1912, and 1924 (May and December) elections were all known by around noon the next day.
The results for the 1920 elections took considerably longer, they were reasonably certain (though not yet official) by early June 9th. Election had been on June 6th.
For the elections of 1928 and 1930, I could not find the time when the official preliminary results were published. According to Joachim Fest, "Hitler", Ullstein 2005, p.420 the results for the 1930 election were ready by 3:00 a.m. the following day. As pointed out in my question, I consider Joachim Fest to be a relatively reliable author, but the topic of the work is not the history of vote counting, so IMHO this timespan is not really set in stone.
So in Germany, vote counting or processing seems to have become considerably faster from 1898 to 1907, and again a lot faster in the late 1920s (assuming that Fest is reliable and is using the same kind of result that the newspaper uses, which for the 1924 elections are "Vorläufiges Gesamtergebnis" / preliminary end result).
(*) the 1907 paper has an analysis article which says "the result of the election is not entirely clear yet" right next to the results. My interpretation is that maybe the analysis article refers to runoff elections, or that the results came in right before the paper was run to the printing press.