When years are (or were) written using kanji numerals, what are the usual variants/options?


I believe that these days, years would be written almost always using
western/Arabic numerals in either the Japanese era or Gregorian calendar.

But it must sometimes be written using the kanji numerals. In historic or
traditional contexts. At least before western influence arrived.

So I'm assuming it would mostly be the Japanese era calendar when it is done.

But when it's done is it done using just the basic digits 一二三四五六七八九十 or does
it also use the characters for thousands and hundreds 千百 etc?. And is a zero
character used, and if so is it 〇 or 零?

Would the "financial" kanji for digits 壱参肆伍陸漆捌玖 ever be used to write years?

And if the Gregorian/western calendar is ever used when writing dates in
kanji, like above, which way are the years written?

(I'm making an app for language enthusiasts and language learners and want to
include as many variants that make sense but not any absurd combinations that
have never been used.)




Japanese eras count starting from year 1, and historically [most of them were
less than 10 years long](https://en.wikipedia.org/wiki/Japanese_era_name)
(some of them didn't even last a full year!), so these issues would have been
moot most of the time. The [昭和]{しょうわ} era was the longest in history, at 64
years; thus there would never have been a question of using 千 or 百.

Some quick web searching implies that e.g. Meiji 40 (1907) was definitely 明治四十
and not 明治四〇 nor 明治四零.

I'm not aware of kanji numerals ever being used with the Gregorian calendar,
although of course the kanji 年 is used to mark the value as a year number.




Japanese eras count starting from year 1, and historically [most of them were
less than 10 years long](https://en.wikipedia.org/wiki/Japanese_era_name)
(some of them didn't even last a full year!), so these issues would have been
moot most of the time. The [昭和]{しょうわ} era was the longest in history, at 64
years; thus there would never have been a question of using 千 or 百.

Some quick web searching implies that e.g. Meiji 40 (1907) was definitely 明治四十
and not 明治四〇 nor 明治四零.

I'm not aware of kanji numerals ever being used with the Gregorian calendar,
although of course the kanji 年 is used to mark the value as a year number.

