The picture on the right is of Osman I, the founder of the dynasty that would hold the title of the Caliphate (Islamic unitary state) for hundreds of years, twenty-nine leaders of the Ottoman House would be commanders of the faithful, caliphs, the Ottomans changed history and were the last leaders of the Caliphate (632-1923).
After the end of the 6th century there was a large movement of Turks into the extreme North-East of the Islamic Caliphate, into Transoxania. By the 10th century many of these Turks who originated in central Asia had gone from being protected dhimmis of the Islamic state to Muslim converts, among the first to convert was the tribe of Oguz Turks led by their Khan named Seljuk.
Years later, a branch of the muslim Oguz tribe, mainly descendants of Seljuk broke off in conflict (power struggle as usual) and left to the Abbasid metropolis of Baghdad to work for the most powerful man on Earth at that time, the Caliph. The Caliph used the massive movement of Seljuk Turks in the military, they became the protectors of the Abbasid Caliphate's frontiers.
After fighting numerous wars in service to the Abbasids, the Seljuk Turks eventually wanted their share of power and they occupied Baghdad and blackmailed the Caliph into handing over more power and authority over to them. Tugrul Bey occupied Baghdad in 1055 and due to that the Caliph officially recognized him and his Turks as temporal governors of Mesopotamia and Persia. However that high position was momentary and the Seljuks with their powerful armies advanced North West of Mesopotamia and Persia to Anatolia, where they would settle independently.
The Seljuk Turks continuously gained power and extended the Caliphate's borders in previous Byzantine (Eastern Roman Empire) territory in Anatolia. Thus creating the muslim state of Rum (Rome in Turkish), with two wonderful capitals Iznik and Konya. In fear of Islam, the primitive European empires allied together and invaded the Dar al Islam with the intention of freeing Jerusalem (first crusade) and stop the advancing Turks, however, they failed in fighting the Muslims. This became clear when Saladin conquered Jerusalem in 1187 for good.
While the clash of civilizations between Christian Europe and the Islamic world reached its peak, another Asian barbaric empire was astronomically conquering everything in their way, the Mongols. Already a world empire, the Mongolian Empire's leader Genghis Khan had his eyes set on Europe and conquered most of Eastern Europe with the help of the original Turks back in central Asia. Genghis Khan died in 1227, but his empire continued conquering for a small amount of time. One of the tribes that fought the Mongols in Europe and Anatolia were the Mameluke Turks who appeared near the state of Rum, they continued fighting the Mongols and their remaining forces in Egypt. The leader of the Mamelukes was Ertughrul, accompanied by his son Osman.
As tradition has it, Ertughrul and his army of Turks were roaming the lands in Anatolia when he saw a cloud of dust coming from the horizon, upon finding out that the Seljuk Turks of the state of Rum were fighting a losing battle against the Mongols Ertughrul made a fateful decision to help the Seljuks with his 2000 men. After Ertughrul won the battle and temporarily delayed the fall of the Ruman state to the hands of the Mongols, the Seljuk Sultan showed his gratitude by giving the Memelukes a strip of land. Osman inherited this strip of land and began empire building, as the Ruman Empire began to fall, the Ottomans began to rise.
In the year 1360, Murad I, the grandson of Osman I had his eyes set on the Balkans. By his reign the Ottomans had already conquered part of Serbia and its historic capital Adrianople and part of North West Anatolia, the Ottomans had an increasingly organized military, began using coins and developed a disciplined people. From a conflict with their tribe on who should rule on the borders of Transoxania (near Uzbekistan), to being immigrants and military servants of the Abbasid superstate, to blackmailing and quarelling for more power, to gaining their own state called Rum, to fighting invading European Christians on a crusade alongside the Ayyubid dynasty of the famous Saladin, to fighting Mongols to secure their survival, the Turks were finally in a stable position. Finally these nomads were to begin building an Empire that would grow into the largest in the world by the 17th century.

Murad I (picture on right), conquered Serbian, Bulgarian and Hungarian land in the Balkans and also large part of Anatolia from the powerful turkish beylik (state) of Karaman to add to his newly established Empire. He was an able military commander and set many laws for his nation of muslims, he set up the Divan governmental system in his empire which reflected the democracy and organization in Islamic ruling, only to some extent though. Murad I established two provinces to his empire, Anadolu (Anatolia) and Rumeli (Europe).
In one his large battle with the Serbians, the battle of Kosovo in 1389, Murad I defeated them and their allies of Bulgarians and Hungarians. An angry Serbian nobleman called Milos Obilik stabbed him with a poison knife and killed him. Murad I created the Ottoman Sultanate in 1383, officially making his empire an Islamic state however would not hold the supreme title of the Caliphate (Head of Islamic authority) for another two centuries, after the Abbasids long decline and fall.
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