Zachlumia or Zahumlje, also Hum, was a medieval principality located in the modern-day regions of Herzegovina and southern Dalmatia (today parts of Bosnia and Herzegovina and Croatia, respectively). While sometimes a fully independent or semi-independent Slavic entity, Zahumlje was mainly under foreign powers; the Byzantine Empire, Kingdom of Croatia, Kingdom of Serbia, Kingdom of Hungary, Kingdom of Bosnia and at the end under the Ottoman Empire.
Read more about Zachlumia: Name (Etymology), Geography, Early Slavic Colonization, History, List of Rulers