Castell Dolwyddelen is often regarded as the birthplace of Llewelyn ap Iorwerth whose grandson Llwyelyn ap Gruffydd held it as a stronghold during the Edwardian campaign to conquer Wales. It finally fell to Edward’s forces in 1283 (some say through treachery) and he used it to house a garrison until, when the Welsh coast had been conquered and fortified, he decided that inland castles were not important and abandoned it.
So this castle is genuinely Welsh. Built by the Welsh for the defence of the people of Wales. Even without the massive resources that Edward had the castle is still standing well. That has to be something to be proud of!