In diplomatic history, the Eastern question was the issue of the political and economic instability in the Ottoman Empire from the late 18th to early 20th centuries and the subsequent strategic competition and political considerations of the European great powers in light of this. Characterized as the "sick man of Europe", the relative weakening of the empire's military strength in the second half of the eighteenth century threatened to undermine the fragile balance of power system largely shaped by the Concert of Europe. The Eastern question encompassed myriad interrelated elements: Ottoman military defeats, Ottoman institutional insolvency, the ongoing Ottoman political and economic modernization programme, the rise of ethno-religious nationalism in its provinces, and Great Power rivalries. While there is no specific date on which the Eastern question began, the Russo-Turkish War (1828–29) brought the issue to the attention of the European powers, Russia and Britain in particular. As the dissolution of the Ottoman Empire was believed to be imminent, the European powers engaged in a power struggle to safeguard their military, strategic and commercial interests in the Ottoman domains. Imperial Russia stood to benefit from the decline of the Ottoman Empire; on the other hand, Austria-Hungary and Great Britain deemed the preservation of the Empire to be in their best interests. The Eastern question was put to rest after the First World War, one of the outcomes of which was the collapse and division of the Ottoman holdings. Background The Eastern question emerged as the power of the Ottoman Empire began to decline during the 18th century. The Ottomans were at the height of their power in 1683, when they lost the Battle of Vienna to the combined forces of the Polish–Lithuanian Commonwealth and Austria, under the command of John III Sobieski. Peace was made much later, in 1699, with the Treaty of Karlowitz, which forced the Ottoman Empire to cede many of its Central European possessions, including those portions of Hungary which it had occupied. Its westward expansion arrested, the Ottoman Empire never again posed a serious threat to Austria, which became the dominant power in its region of Europe. The Eastern question did not truly develop until the Russo-Turkish Wars of the 18th century. According to Karl Marx's writings around the Crimean War, the main factor of the Eastern question was Russian imperialism towards Turkey—with Turkey being a barrier that would protect the rest of Europe, and thus