So during an upgrade to EPiServer 5, I ran into this problem where the culture was wrong and all translations were being translated to English instead of Swedish, this even though the web.config was correctly changed to ”sv-SE”.
After som trial and error I got to set the culture in onpreinit in the a class that inherits templatepage like this
The problem was that only the dates were being formatted correctly, but the translation was still wrong. CurrentPage.LanguageID was not of much help either as it was set to english. At last I found out that you just need to send the short version of the culture to make it work. i.e
This did the trick and now everything is in the right format.