The First Crusade
The Capture of Nicaea
They left in various groups around the end of April
Their first major stop was the city of Nicaea, Kilij Arslan's capital. After a short siege, the city fell. The Byzantines got in first and raised their flag, and they refused to let the Crusaders sack the city. Since plunder was a major source of income (and this crusade was turning out to be expensive), and since looting a city was a traditional practice, the westerners found yet another reason to resent "Greek treachery".
Disagreements were so sharp, in fact, that the Crusaders left Nicaea in June without Greek assistance, except for a few guides. They headed across the interior of Turkey, known as Anatolia.
Kilij Arslan was determined to be revenged for the loss of his city. Fairly early in the Crusaders' march, he offered battle, near the little town of Dorylaeum, in northern Anatolia. After an all-day battle, the Crusaders, though heavily out-numbered, routed the Turks.