The lion and the unicorn are the heraldic supporters of the royal coat of arms. The lion represents England, while the unicorn stands for Scotland. This current combination of supporters dates back to 1603 and the accession of James I of England or James VI of Scotland depending upon your viewpoint. There is a fine example of James’ coat of arms in the church of St John the Evangelist, Leeds.
Earlier kings used different supporters. Tudor kings used a Welsh dragon and sometimes a greyhound. Richard II used a white hart. In addition, the arms have changed over the centuries as Ireland, Scotland and Wales were added.
The royal coat of arms in its various guises, usually supported by a lion and a unicorn, began to appear in English churches and cathedrals in the aftermath of the English Reformation – a reminder to congregations that the monarchy was in charge of matters spiritual as well as temporal. There was never a law, although the “great council” issued an “injunction” in 1660 (Records of Buckinghamshire, p386) to say that churches required coats of arms, they tended to be put on display during times when it was sensible to demonstrate loyalty to the crown– after the restoration of Charles II; in the aftermath of the Jacobite uprisings and upon the accession of a new monarch for example.
This means that the coats of arms on display are not always the same. The arms on display in Halifax date from the reign of Queen Ann, while in Woodkirk near Morley the arms are those of King George I.
Not every church and cathedral has a royal coat of arms. The Victorians got rid of many of them or consigned them to less prominent positions. Apparently there are even one or two arms where thrifty churchwardens turned the board around and painted ones on the back.
The Churches Conservation Trust provides an interesting summary of the way in which the royal arms changed over the centuries with examples. Double click on the image of the fairly rare King Charles I coat of arms that was added to St Cuthbert’s in Wells in 1631 to open the page.