Princess Lilian and Prince Bertil finally married in 1976, following a relationship of more than thirty years.
Bertil's father, King Gustaf VI Adolf, had ordered him to abstain from marrying commoner Lilian.
The couple were finally give royal approval to marry by King Carl XVI Gustaf, who took the throne in 1976.
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Aaron Ramsey has told his English team-mates at Arsenal to beware Wales overtaking them in the FIFA rankings.
Plenty of fine dry weather to come today and prolonged spells of sunshine. A cool easterly breeze will take the edge off the temperatures.
The three-day event in the Welsh capital is expected to attract more than 20,000 visitors.