Which battle in 1097 marked a major victory for the First Crusade over the Seljuks?

The Battle of Dorylaeum was the 1097 battle that marked a major First Crusade victory over the Seljuks.

It was fought on 1 July 1097 near Dorylaion in Anatolia, close to modern Eskişehir, Turkey. After capturing Nicaea, the Crusader army divided into columns while crossing Asia Minor. Sultan Kilij Arslan I attacked Bohemond of Taranto’s isolated vanguard with mounted archers, nearly overwhelming it.

The Crusaders held a defensive position for hours until reinforcements led by Godfrey of Bouillon, Raymond IV of Toulouse, and others arrived. A later attack, including an outflanking movement associated with Bishop Adhemar of Le Puy, drove the Seljuk forces from the field. The Crusaders also seized the sultan’s abandoned camp and treasure.

Dorylaeum is often confused with Nicaea, which was a siege and surrender earlier in 1097, or Antioch, whose famous siege came later. The victory opened much of Anatolia to the Crusaders’ advance toward Antioch, although it did not end Seljuk power in the region.