China and Japan have Sunday as the first day since the 4th and 8th century respectively: http://chartsbin.com/view/41671.
So presumably, you come from a Europe-centric view: http://chartsbin.com/view/41671
So presumably, you come from a Europe-centric view: http://chartsbin.com/view/41671
https://unicode-org.github.io/cldr-staging/charts/38/supplem...
Note that common usage and the official definition may well differ. Most Americans probably consider Monday the "first day of the week" as it is the first day in a standard work week. But officially, Sunday is the first day of the week.
Why does the US think that the week starts on Sunday?
I've read some historians state that Christians started using Sunday as their Sabbath day in order to distinguish themselves more sharply from the Jews.
There are some Christian denominations which use Saturday as their Sabbath day, such as Seventh-day Adventist Church, so using Saturday as the holy day is a minority practice among Christians but it's a significant minority.
this change to starting the week on monday is therefore a recent development.
same in china btw. days in china are numbered. monday is number 1, and sunday is 7. so while people may have the idea that the week starts on sunday (i don't know) the day numbering suggests that it actually starts on monday.
same goes for europe. monday by law and sunday by tradition
My understanding is that all days except Sunday "week-day" (星期日) are numbered. Monday is (星期一) "week-one". So there is still some room for ambiguity left if you allow for counting from 0.
I'm an iOS developer, and whenever I print dates, I just ask the system to print it, according to the system its locale.