Vivat Regula Variatio!

 As a Latinist and a Christian, my pronunciation loyalties are divided according to the occasion. When I read Classical texts, I generally use the Erasmian pronunciation, but when I read Christian texts, devotionally or otherwise, I prefer the Ecclesiastical pronunciation. These, however, are but two of the historical options for Latin pronunciation - musician are familiar with a third, more Teutonic variety. The French also insist on doing diction according to their own customs. Yet each country within Christendom, until the Reformation, treated the more common Latin phrases as a register of the vulgar tongue rather than an elevated idiom, by which mechanism many Latin terms were nativized. Legal formulae, in particular, have a tendency to evolve and then resist further evolution; thus the traditional English pronunciation of vivat in the formula vivat rex fossilized as waiwat rex. If the absence of v is surprising, recall the following facts: firstly, English words beginning with v are almost exclusively borrowed from French whereas w was a native English sound, and secondly, the letter u for many centuries represented both u and w as well the introduced v.

To say that the Coronation was scripted would be an understatement. The Coronation of Elizabeth II included vaivat rejaina - not identical, but note the diphthong.The choice of waiwat over vivat emphasizes the traditional, royalist, Latinate, theocratic, catholic (but not Catholic) nature of the British monarchy.