The fall of the Ottoman Empire

The Ottoman Empire has shaped the history of modern mankind from the seige of cantanstinople to world I and world war II . 

The Ottoman Empire was a thistle in the underbelly of Europe. Aside from the conspicuous social and religious contrasts that made most European forces unfriendly to them, the were likewise specifically hostile to European exchange with the Orient. Besides, they had overexpanded and the populace in most Balkan posessions was antagonistic to Ottoman occupation. They ought to have been steered sooner. 

The reasons that permitted the Ottomans to achieve that far into Europe are: 

The undermining of the Byzantine Empire by the European powers between 1200-1453. 

Religious strife in Europe, created by the Reformation, disconnecting the Catholics and giving European partners to the Ottoman Empire. 

Strategic maneuver between the European forces: 

Between 1683 (Battle of Vienna) and 1923, we are discussing 240 years of decrease of which the primary half (until 1804 when the Serbs revolted) were spent without Ottoman power being truly challenged, spare by the Russians. Their other extraordinary foe, the Habsburgs were content with the domains yielded then. Venice had declined before the Ottomans did. The other european forces, utilized them shrewdly as a partner every once in a while, against Russia or the Habsburgs. They likewise utilized the subject countries desires for freedom, without commiting to bolster their rebellions to fulfillment, until 1830. After 1830, the European forces propped up the OE on the grounds that they were anxious about the possibility that that an adversary would profit more. In this structure we can likewise include the accompanying optional reasons: 

No more Crusades: The Reformation made them inconceivable. The partnerships that battled against them in 1571 and 1683 were restricted. 

Misusing the Orthodox Church: By allowing religious resistance and supporting the Patriarchate in its battle for impact against Rome and later against the autonomous Orthodox Churches, the Ottomans kept their Orthodox subjects from straightforwardly adjusting themselves to any western power, at any rate until Russia challenged them. 

National freedom was seen as a risk: 

The real European forces were governments that by definition contradicted the Enlightenment thought of national freedom; henceforth they were threatening to any repulsive countries inside the OE. Just Napoleon's France was ideologically in support and they figured out how to foul things up enough for the Ottomans in two short decades. 

The Age of Exploration and imperialism: 

Despite the fact that the revelation of the New World and the foundation of pilgrim domains undermined the Ottoman economy on the grounds that the significance of their key position in exchange reduced and in light of the fact that their coin was degraded because of expansion from the flood of Spanish gold, imperialism moved the concentration of European powers far from the Orient. Likewise until the nineteenth century there was little enthusiasm for cutting out customer states (provinces) off of the Ottoman regions. 

The Mongols settled down: 

From the beginning of history until the fifteenth century, every real domain in Eurasia were under danger from attack by moving populaces in focal Asia. The Ottomans just confronted one such attack, by Tamerlane in 1400 and they scarcely survived it. After that, these attacks stopped and the Mongols got to be partners of the Turks in their wars against Russia and Persia. 

Istanbul 

Another reason, which may have propped up the OE if there should be an occurrence of a staggering attack shape either East or West, is the fantastic protective position of its capital. Constantinople had been the primary reason the Byzantine Empire had delayed until 1453, so Istanbul could have assumed a similar part for the Ottomans. We will never know for certain, however perceiving how wretchedly the Russians neglected to achieve it in the eighteenth century and the catastrophe the forces of the Entente had in Gallipoli amid WW1, we have a solid sign.

Source :- https://www.quora.com/What-led-to-the-decline-of-the-Ottoman-Empire

Source :- https://en.wikipedia.org/wiki/Historiography_of_the_fall_of_the_Ottoman_Empire