Sorry for the reply, but couldn't see a way to edit my post
I have also tried to set the culture programmatically rather than via the markup and the grid still appears to be in english
Here is the code I have tried
uxQuestions.Culture = CultureInfo.CreateSpecificCulture("de-DE")
uxQuestions is a "Protected WithEvents uxQuestions As Global.Telerik.Web.UI.RadGrid"