AEIOU sequence

[RenegadeHealer]

It also has Greek, Arabic, and Hebrew alphabets.

Don't forget Armenian, too. (For the sake of all you Anania Shirakatsi fans out in Voynichland!)

I'd like to point out that a thorough walk around the Old City of Jerusalem would carry a high probability of encountering signage with all four of these writing systems (in addition to the now-ubiquitous Roman alphabet, of course), at least when I visited it in 2010. I imagine the same would hold true when Frederick III made his pilgrimage there as a young man. Plus, a literate man of noble standing, who arrived in Jerusalem as an honored guest of a local in good standing, would have easily had access to documents and books written in all five of these writing systems, plus a few more (Kartvelian, Syriac Estrangelo, Glagolotic, perhaps Mandaic, perhaps a few ancient scripts no longer in use by that point).