Āraiši lake fortress was built and inhabited in the Viking Age (9th–10th cent. AD) by the Latgallians, one of the ancient Baltic groups. In the middle and second half of the 1st millennium AD, the Latgallians arrived in the northern part of present-day Latvia, previously populated by people belonging to Finnic groups. The newcomers needed well-protected sites where settlements could be rapidly built. Islands and shallows in lakes were excellently suited for this purpose. There were also social reasons behind the establishment of lake settlements. The excavated material shows that Āraiši lake fortress was the residence of a member of the uppermost stratum of Latgallian society, where he lived together with his kin and other dependants.
Āraišu ezerpils: Teikas un vēsture (Jānis Apals, Mārtiņš Zelmenis). Rīga, 1998. pp. 11–29.