[4] Erik's Chronicle was written at the period of Swedish conflict with Novgorod, which at the time included Karelia, so blaming the raid on them may have been a way to justify attacks in the 14th century.
[8] Karelians were not normally described as pirates in written sources, and historian Hain Rebas has questioned whether the ships they commonly used on the Lake Ladoga were even suited for sailing to Sigtuna.
[9] Russian chronicles also do not tell of spectacular naval expeditions conducted by the Novgorodians; instead, there are mentions of merchants and princes visiting countries overseas.
[11] 17th-century historian Johannes Messenius mentions the raid in his Scondia illustrata, blaming it in different parts of text once on Curonians and once on Estonians.
They sailed into Lake Mälar from the sea whether calm or stormy it might be, secretly within the Svealand isles in stealthily advancing files.