Vyachko of Koknese

Vyachko of Koknese, also Vetseke of Kokenhusen (Latin: Rex Vesceka de Kukenois,Latvian: Vetseke, Russian: Вячко) was the ruler of the Principality of Koknese in present-day Latvia, a vassal of Polotsk, who unsuccessfully tried to establish himself as a local ruler first in Latvia and then in Estonia, and fought against the expansionism of the Livonian Knights at the turn of the 13th century.

His name is the Old Novgorod dialect form of Vyacheslav.

According to Russian sources, his father is supposed to have been a Rurikid prince of Drutsk. Another interpretation, based on evidence from the Chronicle of Henry of Livonia, is that he came from a local élite, perhaps a Livonian, who converted to Orthodox Christianity and became a vassal of Polotsk, whereupon he changed his name to the East Slavic Vyachko.

The Chronicle says the population of Koknese included Balts (Latgallians and Selonians) and even a German colony, in addition to the East Slavic element.

At the beginning of the 13th century, when during the Northern Crusades Germans led by bishop Albert of Buxhoeveden and the Livonian Brothers of the Sword began to establish themselves on the shores of the Gulf of Riga, Vetseke ruled the fortress of Koknese some 100 km upstream of the Daugava.

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