Caernarfon used to be the ancient capital of Wales (Cardiff became the capital only in 1955). The castle was constructed for Edward I (late 13th c.) to ensure his position in Wales after his armies had defeated the last Welsh Prince (Llywelyn ap Gruffydd, 1283). Edward I brought his wife, pregnant with their first child, so that she would give birth here (the castle wasn't near ready yet), fulfilling thus a Welsh legend promising a Welsh Prince who would save the people of Wales Baby Edward (the future Edward II) was proclaimed Prince of Wales here in 1301. Since then the title is given to every first born son of the King or Queen of England.