Ala ad-Din Tekish or Tekesh or Takesh (died 1200) was Khwarazm Shah from 1172 until his death. He was the son of Il-Arslan

Il-Arslan

Il-Arslan was Khwarazm Shah from 1156 until his death. He was the son of Atsïz.In 1152 Il-Arslan was made governor of Jand, an outpost on the Syr Darya which had recently been reconquered, by his father. In 1156 Atsïz died and Il-Arslan succeeded him as Khwarazm-Shah...

. His rule was contested by his brother, Sultan Shah

Sultan Shah of Khwarezm

Sultan Shah was a claimant to the title of Khwarazm Shah from 1172 until his death. He was the son of Il-Arslan.In 1172 Il-Arslan died and his sons began fighting over who would succeed him. Sultan Shah was the younger son, but he was considered the formal heir and his mother, Terken Khatun,...

, who held a principality in Khorasan. Tekish inherited Sultan Shah's state after he died in 1193.

In 1194 Tekish defeated the Seljuq

Great Seljuq Empire

The Great Seljuq Empire was a medieval Persianate, Turko-Persian Sunni Muslim empire, originating from the Qynyq branch of Oghuz Turks. The Seljuq Empire controlled a vast area stretching from the Hindu Kush to eastern Anatolia and from Central Asia to the Persian Gulf...

 sultan of Hamadan

Hamadan

-Culture:Hamadan is home to many poets and cultural celebrities. The city is also said to be among the world's oldest continuously inhabited cities.Handicrafts: Hamadan has always been well known for handicrafts like leather, ceramic, and beautiful carpets....

, Toghrul III, in an alliance with Caliph Al-Nasir, and conquered his territories. After the war, he broke with the Caliphate and was on the brink of a war with it until the Caliph accepted him as Sultan of Iraq, Khorasan, and Turkestan in 1198.

He died of a peritonsillar abscess

Peritonsillar abscess

Peritonsillar abscess , also called a quinsy or abbreviated as PTA is a recognised complication of tonsillitis and consists of a collection of pus beside the tonsil .-Symptoms and signs:...

 in 1200 and was succeeded by his son, Ala ad-Din Muhammad

Muhammad II of Khwarezm

Ala ad-Din Muhammad II was the ruler of the Khwarezmid Empire from 1200 to 1220. His ancestor was a Turkic slave who eventually became a viceroy of a small province named Khwarizm. After his father died, Muhammad inherited his father's lands, and it was from there he began expanding outwards...

.