[3] It was situated in a safe place near the royal castle, on the island in the branches of the Warta River; the town had no walls but only two gates.

16–18] In 1410 Koło was a gathering place of the Greater Poland nobility, which called for a war with the Teutonic Order (see Battle of Grunwald).

In 1452 the Royal Castle in Koło was the place of meeting between King Casimir the Jagiellonian and the representatives of the Prussian Union (see: the Thirteen Years' War).

From the early 15th century until 1716, Koło was the meeting place of the Provincial Parliament called Sejmik Generalny for the Greater Poland region, comprising the Poznań Voivodship, Kalisz, Sieradz, Łęczyca, Brześć Kujawski and Inowrocław Voivodeships.

[9] In November 1939, Poles from Koło were also murdered in other places, including Bugaj, Chełmno nad Nerem, Konin.

[13] The remaining Jews were deported to Chełmno extermination camp, where they were killed in gas vans and buried in mass graves.

Koło remained a transfer point for Jews deported to Łódź, and Nazi officials, including Heinrich Himmler, visited the town.