British officials in June 1976 feared they had embarrassed then Crown Prince Akihito and Princess Michiko by subjecting them to a rather unrefined medieval banquet during their trip to Britain, according to files released to Kyodo News under freedom of information laws.

In a review of the visit sent to the British Embassy in Tokyo from the Far Eastern Department in London, officials said that while the couple were impressed with the entertainment at Cardiff Castle in Wales, "they found it rather strange to have to eat with their fingers, with bibs round their necks, and to drink sweat mead while the compere made occasionally risky allusions."

The "friendly and informal" evening of folk dancing and singing was held in the cellars of the castle and was hosted by Foreign Office Minister and Deputy Leader of the House of Lords Lord Goronwy-Roberts.

The Foreign Office dispatch was sent to the Welsh Office and resulted in the department's chief bureaucrat deciding that this would be the last time a medieval banquet was laid on for important visitors.