The Russo-Turkish War began in 1787 when war was declared between Russia and the Ottoman Empire. Austria, allied with Russia, came to its aid. In the first months of the war the Ottomans advanced through the Austrian lines, driving defenders out of Manat. An Austrian army was moved through Serbia and Transylvania, beating back small Ottoman skirmishers. In fall of 1789 Ernest Gideon von Laudon took control of the main Austrian army in Moldavia, entering Ottoman Bosnia.