Possible Clues:

• Rulers of the Nemanjic dynasty, e.g.
• Early-19th-century Ottoman Empire foes
• Belgradians
• Kosovo people
• Some Balkans
• Rod Blagojevich's parents, e.g.
• Neighbors of Croats
• Nikola Tesla, et al.
• Certain Novi Sad residents
• Niš natives