In 1397, the Carthusians founded a monastery here, Ahrensbök Charterhouse, which helped the place grow in prominence.

In 1564, the Amt Ahrensbök, or district of Ahrensbök, was established as a civil administration unit, and between 1593 and 1601 a castle was built, Schloss Hoppenbrook, on the site and with the materials of the charterhouse, which had been secularised in the 1580s during the Protestant Reformation and subsequently demolished.

During the Second Schleswig War of 1864 Ahrensbök fell for a short time under the control of first the Austrians and then the Prussians.

In the same year, after the Austro-Prussian War, the district of Ahrensbök was given to the Grand Duchy of Oldenburg as compensation for their hereditary claims on the newly-Prussian territory of Holstein.

[2] After World War II thousands of displaced persons and refugees were resettled here: the population rose from 5,063 in 1939 to 10,169 in 1950.

Since March 1985 the local government administration of the Gemeinde has been accommodated in the new town hall (Rathaus) near the site of the former castle and the Amtshaus (demolished in 1983).