What is "buzhans"

The Buzhans or Buzhane (, , ) were one of the tribal unions of Early Slavs, belonging to the Northern group of Slavic culture. They are mentioned as Buzhane in the Primary Chronicle. It appears that the name of the tribe derives from the Western Bug, in Ukraine, where they chose to settle down. According to the Bavarian Geographer, the Buzhans had 230 "cities" ( fortresses). Some historians believe that the Buzhans and the Volhynians used to be called the Dulebes.