"Ottomanvictory" . . . "*Serbia becomes vassal state of the Ottoman Empire" . . "unknown" . "unknown" . "*Ottomans invade Bosnia" . . . "15\u201320,000" . . "Siege of Golubac"@en . . . "The Siege of Golubac (Hungarian: Galamb\u00F3c) was a military conflict between the Hungarian\u2013Wallachian\u2013Lithuanian alliance and the Ottoman Empire in May 1428. This siege was the first battle in the Hungarian military history, when the Hungarian army used significant artillery. However, they could not capture Golubac as it was defeated by the Ottoman main army, led by Sultan Murad II. After the battle, most of Serbia and Bosnia was conquered by the Ottoman Army."@en . "20pxGrand Duchy of Lithuania" . . . "20pxWallachia" . "20pxKingdom of Hungary" .