The Ottoman state grew under Bayezid I. He fought many wars in the Balkans and Anatolia. This happened over 13 years. The Kapikulu corps got bigger. Many people did not like this. They felt left out. The taxes also went up. This made the Turkoman lords very angry. They felt threatened by the strong army. Many people in Anatolia did not like Bayezid I. Some Turkoman beys asked the Timurid Empire for help. Timur was a strong leader. He had just won many wars in Iran and Azerbaijan.
Timur wanted to help the Turkoman beys. He was happy to be their friend. This was bad for Bayezid I. He was too confident in his army. A big war happened at the Battle of Ankara in 1402. Timur's army was much bigger. They won the war. Many Turkoman beys switched sides. Bayezid I was captured. The Ottoman army lost because of divided loyalties. The central state was changing too fast.
The rest of the century was marked by competition between two groups. One was the Devşirme and Kapıkulu in the Balkans. The other was the provincial Turkic group in Anatolia. This competition would shape the future of the Ottoman state. The military transformation had a big impact. It changed the way the state worked. The social groups were affected too. They had to adapt to the new changes. The standing army became more important. The nomadic army was still strong. The conquest of new lands continued. The alliance between Timur and the Turkoman beys was a key factor. It led to the defeat of the Ottoman army.
