Unfortunately, the previous book didn't elaborate on what the Arisen is. It was simply one of the many titles of previous kings, usually followed by "earned by defeating the beast so-and-so the great and terrible". The main inconsistency was that it seemed the Erod gained this title [i]before[/i] sealing the dragon, whereas it's implied that the other kings gained the title after the fact. Either way there wasn't any further information from the previous book. Even when you ask the acolyte, he takes some time to search but unfortunately the best he can bring is a few books about various heroes, and none of them mention the Arisen at least not in the titles or prefaces. You could try to read all of them, but there were at least eleven more books, and each one much thicker than the previous two you had. At least three hundred pages each.