The Siege of Solitude was the final battle in the War of the Red Diamond between the Kingdom of Solitude and the Septim Empire. The War of the Red Diamond began when Potema Septim was banished from the Imperial Court and Kintyra Septim was named the Empress of Tamriel. As time went on, Potema executed Kintyra at the city of Glenpoint, and Potema's son, Uriel Septim III was killed in a riot in the city of Gilane. Potema's allies soon lost hope of her and left her to her madness. The war soon arrived in the Kingdom of Solitude and the city-state itself. Potema was already seventy years old, and her brother, Cephorus Septim was crowned Emperor ever since Kintyra's death.
The battle was a sure victory for the Empire, Potema had to resort to necromancy to keep the Empire at bay, but alas, it was not enough. She died on her bed with a grimacing smile before the Siege could get to her. The siege had lasted for a month. Before she died, she had secretly given Pelagius Septim III an amulet originally from her father, Pelagius Septim II. This amulet changed Pelagius severely causing his mind to fall asunder. With her death, Pelagius was named the new King of Solitude and was eventually given the name, Pelagius the Mad.