Kung grattis is a swedish intentional mistranslation of 'congratulations' (accurately translated to 'gratulerar' or 'grattis') where the extra "kung", meaning "king", applies a majestic weight to the wishings. Kung grattis is widely used ironically.
1) Ironical usage:

- Why so somber, mate?
- Just told Anna about Sarah.
- Kung grattis...

2) Used as sincere congratulations:

- Tillåt mig att kunggratulera! Du har vunnit en brödrost med inbyggda blinkers!
by Papy Jojo March 16, 2007
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