Opposite the mansion, in a depression on the other bank of the river, was the old castle of Bunkenburg which lies today in ruins.

The present house was built in the 16th century on the river bank by Ahlden opposite the Bunkenburg.

The west wing is the main building of the mansion, which Duke Christian the Elder of Brunswick-Lüneburg had built by his seneschal (Drost), Johann Behr, in 1613.

The north wing is a timber-framed structure that was redesigned in 1705 by the architect, Johann Caspar Borchmann, because the building was falling into disrepair.

The castle's predecessor, Bunkenburg, appeared on the opposite bank of the Aller, a detail also mentioned by Merian.

The occupants of this castle were the House of Ahlden, first mentioned in the 13th century, who were knights (Ritter) and Burgmanns.

After about 450 years in existence, the Amt of Ahlden was disbanded in 1884 and its function was transferred to the district of Fallingbostel.

In the Thirty Years' War the house was occupied by the imperial troops under Tilly after a day's siege.

The considerable renovation work required was completed in 1975 at a cost of 90,000 DM from state funds.

When she was divorced from her husband in 1694 after her affair with Lieutenant Königsmarck, Sophie Dorothea of Brunswick-Lüneburg was brought to Ahlden House, where she was imprisoned until her death in 1726.