At various points throughout its millennium-long history, the Ottoman Empire controlled vast areas of territory.  The Ottoman Empire reached its greatest westward extent in the seventeenth century.  In 1683, the Ottomans laid siege to the city of Vienna.  Though they were ultimately unsuccessful, the fact they did so serves as testament to their influence and power in European affairs.  Until 1571 at the Battle of Lepanto, the Ottoman Empire enjoyed considerable influence on the eastern half of the Mediterranean Sea.  After these two defeats, the power and influence of the Ottoman Empire began to wane in the west. 

It would take somewhat longer for the Ottoman Empire's power to decrease in the east and in the south.  Rather than there being very decisive battles that crippled the Ottomans, there were a number of smaller engagements over the span of years, resulting in a series of defeats that began to eat away at Ottoman control.  It was not until the end of the First World War that the Ottoman Empire crumbled. 

At its highest point during the late fifteenth and sixteenth centuries, the Ottoman Empire spanned from Eastern Europe in the West, to Egypt in the South, and to Central Asia in the East.  At no other point in its history did the Ottoman Empire control as much territory and enjoy as much influence as they did during this 175-year period.