Language
There are two tongues that traverse the surface of Bedwar Barthu Dirio, of which the first, common, tongue is called Chomin Balog, and is the language of everyday communication. Used by traders, commoners, peasants, it is the day to day dialect of the populace in every city. Even those within the government bureaucracies find themselves speaking in that voice. Effectively, it is the language through which all of the countries upon Bedwar Barthu Dirio communicate, and it is slowly driving the other language to extinction.
That other language is called Dal Cymraeg, but it is sometimes known as the 'Language of Naming', for that is now its primary purpose. Few people speak Dal Cymraeg any more, and those who do tend to be mages and other highly educated individuals seeking to hold onto a measure of exclusivity, holding themselves above and beyond the commoners who speak in a different tongue. Despite the disappearance of Dal Cymraeg as a spoken language, almost everyone is named in that tongue, although most of the people who are so named these days must speak to a scholar or a translator to find an appropriate name for their child.
The only other major usage for Dal Cymraeg is the recording of court and other official documents, and it is in those written commentaries that the language still maintains its strongest hold. Without those, it would soon disappear and be overcome by Chomin Balog, and even with them, its grip would weaken further.
Scholars of Bedwar Barthu Dirio are uncertain as the origin of the two languages that reign within the four corners of the continent, but they can all agree on one thing: that neither relates in any way to the other. One sits within a completely different language structure from the other, and the only information that scholars agree on is that both evolved at the same time, all across the land, for nowhere can researchers find documents of an age that does not possess evidence of both tongues. In light of certain recent discoveries, this might pose an interesting dilemma.