... But this is Greek Orthodoxy ... Greek Orthodox priest
Greek Orthodoxy split with Rome in the year 1054, that was even before the battle of Hastings (1066).
Philip, duke of Edinburgh
Encyclopædia Britannica Article
born June 10, 1921 , Corfu, Greece in full Prince Philip, duke of Edinburgh, earl of Merioneth and baron Greenwich, also called Philip Mountbatten, original name Philip, prince of Greece and Denmark husband of Queen Elizabeth II of the United Kingdom.
Philip's father was Prince Andrew of Greece and Denmark (18821944), a younger son of King George I of the Hellenes (originally Prince William of Denmark). His mother was Princess Alice (18851969), who was the eldest daughter of Louis Alexander Mountbatten, 1st marquess of Milford Haven, and Princess Victoria of Hesse.....
The English Church was out of communion with the Roman Patriarchate from 1052, and thus was not anathematized by Patriarch Michael in 1054. The Norman army invaded England with a 'blessing' to reduce the English Church to Papal rule.
There is moreover circumstantial evidence to suggest that the filioque was not used in the English Church until the Norman conquest, which is strenghthened by the indisuptable fact that most Saxons fleeing the Norman invasion settled in Orthodox lands, many going to Constantinople, some, including King Harold's daughter, to Kiev (she married Prince Vladimir Monomach!)
Of course the post said "of his fathers": Prince Charles' father is Greek, and was raised Orthodox, converting to Anglicanism only to marry into the British Royal House.
Incidentally, Orthodoxy long present in England in minority immigrant communities has been revived in Britain by conversions among those of Celtic, Saxon and Norman ancestry. Orthodoxy is now the largest religious grouping in Walsingham, the site of the principal Marian shrine in England.