First time noted in early 12th century in Gallus Anonymus Chronicle. At this time Czarnków was grad of pagan Pomeranians and was ruled by local Pomeranian ruler Gniewomir. It was conquered by Polish prince Bolesław III Wrymouth in 1108. From 1244 until 1407 Czarnków was the seat of a castellany. From early 14th until the middle of the 17th century Czarnków was in the hands of the noble family of Nałęcz (they changed name for "Czarnkowski"). The Czarnkowski family build a new castle (first time noted 1331 and destroyed at the end of the 17th century) and established before 1369 town privileges. From 1772-1919 the town belonged to the Kingdom of Prussia and Imperial Germany. After World War I the town became part of the Second Polish Republic.