He was most likely born in the Swedish settlement of Kaup in modern-day Kaliningrad, presumably a descendant of Varangians who participated in the founding of Kievan Rus’.

[3] He became an ardent Christian and a friend of Albert of Buxhoeveden, Bishop of Riga, who, in 1203–1204, took him on a journey to Rome and introduced him to Pope Innocent III.

The Pope was impressed by the converted pagan chief and presented him a Bible, hundred gold pieces, ennobled him and gave him the name “Lieven.” When he returned from the journey, his tribe rebelled against him and Caupo took part in a siege of his former fortress in Turaida in 1212.

Modern Estonians, Latvians, and remaining Livonians do not have a singular view about the historical role of Caupo.

Baltic nationalists generally consider him a negative figure and a traitor to his people, however, such claims are sometimes dismissed by scholars as applying a modern viewpoint to a medieval chieftain.