Blain was in the past one of the most important places in Brittany... The castle was raised by Alain Fargent, duke of Brittany, in 1105. It's a big quadrilateral which used to be surround by a wall flanked by 9 towers.
The first wall had 4 towers: Mill's tower (north-west), demolished in 1591; Weapons keep's tower (south-west); Clock tower (south-east); Constable's tower, raised between 1380 and 1383 by constable Olivier de Clisson. The second wall was reinforced by 5 towers.
The first mention of Blain's lords dates back to 1090, with Guégon. Then, Hervé of Blain in 1203 and Olivier de Clisson inherited the castle at the end of the 13th century. During Brittany Succession War, Philip of Valois, who supported Charles de Blois, confiscated Blain in 1341.
But the Montfort members re-took it. Meanwhile, Clisson left Blain for his Josselin castle. By marriage, Blain castle fell to the Rohan family, when Clisson's daughter married viscount de Rohan (famous family, who kept the castle until 1802).
Did you know duchess Ann of Brittany often came in Blain, even for one month, just before her marriage with king Louis XII? The viscount was her uncle... A Rohan member rebuilt the chapel and the Renaissance main building. He added high walls surrounding his estate and put deers (300 animals) in the park for his shooting parties.
In 1586, the duke de Mercoeur besieged our fortress, then he was expelled by a sir called Goul 3 years later. After the war of religion, king Louis XIII punished the duke de Rohan, because this one had embraced the Reformed religion in 1628: the castle was demolished.
During the French Revolution, the apartments were devastated, the archives burnt... Did you know they wanted to raze the ruined castle? But they needed men and money for that... They gave up... fortunately!