In medieval Europe, the coins seem to feature a bewildering array of inscriptions, many of which feature a string of nonsensical letters separated by rosettes or annulets. Much of the time, these letters represent an acronym: the first letter of the words in a Latin phrase. One of these acronyms that fascinates me is the "AEIOU" or "AEIOV" found on some Austrian coins in the mid-1400s.
I believe that this particular acronym was first popularized by King Friedrich III, the Holy Roman Emperor from 1452 to 1493. Interestingly, he even turned the acronym into his monogram and was using this as early as 1440. Wikipedia describes King Friedrich III's his fondness mythical formulas and I could imagine his monogram gracing the cover of an alchemist's book.
Most explanations of this phrase describe how important or powerful Austria was. Here are several versions, in Latin and in English, ascribed to Friedrich III himself (and listed on Wikipedia):
1. Austria est imperio optime unita (Austria is the empire best united)
2. Austria erit in orbe ultima (Austria will be the last (surviving) in the world)
3. Austriae est imperare orbi universo (It is Austria's destiny to rule the whole world)
In Alfred Szego's book, "The Coinage of Medieval Austria 1156-1521", the author offers two more possibilities, in German and English:
1. Alles Erdreich ist Oestereich Unterthan (All Earth is Austria's Ultimately)
2. Aller Ehren ist Oesterreich Voll (All honor is fully Austria's)
It is my opinion that it is more likely that Friedrich III would more likely have used Latin at this time than German (recall that Gutenberg was just getting started with his moveable type in 1439), but these certainly are also potential explanations.
Below please find Friedrich III's monogram and pics of my 1459 kreuzer from Wiener Neustadt, an Austrian duchy. Despite the flan cracks, you should be able to make out some elements of his monogram on the rev. The attribution is Levinson IV-7 and Szego 2L35.
"The danger we all now face is distinguishing between what is authentic and what is performed."