Sometime after the Holy Kingdom of Faerghus gained independence in Imperial Year 751, the Empire constructed the Fortress City of Arianrhod within House Rowe's domain. Upon the city's completion, House Rowe promptly revolted against the Empire and joined the Kingdom, gifting it a valuable bulwark against incursions from the south.
In Imperial Year 1185, Arianrhod became a key objective in the conflict between Fódlan's three countries.
Crimson Flower (Black Eagles)
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Following the Adrestian Empire's war on the Church, the Kingdom of Faerghus allies itself with the Church. Dimitri had Cornelia moved to Arianrhod, accompanied by Rodrigue and several Kingdom soldiers to protect her. Unexpectedly, the Empire attacks Arianrhod, though this is because Edelgard is aware that Cornelia is actually affiliated with those who slither in the dark.
In the ensuing battle, the Empire becomes victorious and leaves behind a garrison to occupy the city. However, Volkhard (who is also known as Thales) has javelins of light burn Arianrhod to ashes, killing many including most of House Rowe's members in response to Cornelia's death.