Why does the item description on an order line appear in the wrong language?

The description is taken from the language set in the shopper's session. If the language looks wrong, the usual cause is a mismatch between the locale code your product source sends and the locale codes configured in Brink. Two-letter and regional variants of the same language are not interchangeable, so a source sending one form while the other is configured will fall back to a different language.

For example on order lines the description of an article is Swedish when it should be Danish.