Chaka of Smyrna

Tzachas
Modern representation of Tzachas in the Istanbul Naval Museum
Died	1093
Nationality	Oghuz Turks

Tzachas (Greek: Τζαχᾶς), also known as Chaka Bey (Turkish: Çaka Bey) was an 11th-century Seljuk Turkish military commander who ruled an independent state based in Smyrna (present-day Izmir). Originally in Byzantine service, he rebelled and seized Smyrna, much of the Aegean coastlands of Asia Minor and the islands lying off shore in 1088–91. At the peak of his power, he even declared himself Byzantine emperor, and sought to assault Constantinople in conjunction with the Pechenegs. In 1092, a Byzantine naval expedition under John Doukas inflicted a heavy defeat on him and retook Lesbos, while in the next year he was treacherously slain by his son-in-law Kilij Arslan I. Smyrna and the rest of Tzachas' former domain were recovered by the Byzantines a few years later, in c. 1097.

Very little is known about his life, and that mostly from only one source, the Alexiad of the Byzantine princess Anna Komnene, daughter of Emperor Alexios I Komnenos (r. 1081–1118). He is also mentioned in the 13th-century Danishmendname, but it is not a very reliable source due to the semi-legendary nature of its material.

According to the Alexiad, Tzachas was originally a raider, who was taken as a prisoner by the Byzantines during the reign of Nikephoros III Botaneiates (ruled 1078–81). Tzachas entered Byzantine service and advanced rapidly through imperial favour, receiving the title of protonobilissimus and rich gifts. However, when Alexios I Komnenos deposed Botaneiates in 1081, Tzachas lost his position and fled Byzantium.