Moon Kingdom

The Moon Kingdom is where the first Silver Millennium was situated. It had a very fairytale like appearance, with a dome situated over the kingdom to produce an artificial climate.Despite the kingdom's mythical appearance, it was advanced in technology, with a computer system named "Eternity Main System". According to Artemis, ice-skating was a very popular sport in which Princess Serenity excelled at. The citizens of the Moon Kingdom had long lifespans and their duty was to guide Earth on the path of evolution and protect the Legendary Silver Crystal, which had been handed down through the royal family.

During this era Endymion, flanked by his four guardians, held the position of Crown Prince of Earth. Despite a prohibition on relations between people of the Earth and the Moon, he and Princess Serenity fell in love. Out of jealousy and under the influence of the evil Queen Metalia, a sorceress named Beryl raised up the citizens of Earth in a war against the Moon. As a result, the Moon Kingdom was completely destroyed, and Earth's history had to start all over again. The war marked the end of the First Silver Millenium.

Queen Serenity used the powers of the Legendary Silver Crystal to seal away Metalia but in doing so used up all her life force.Before dying, the Queen sent the princess, Prince Endymion and her guardians to be reborn in the 20th Century.They were all reincarnated as regular humans with no memory of the prosperous kingdom, but still held their Senshi powers just incase Metalia ever broke her seal.It is implied that Beryl and the Four Shitennou where reincarnated as humans.

After Sailor Moon defeats Metalia, the Moon Castle is resurrected but un-inhabited. Usagi is presented with the option to become the new Queen Serenity but she denies this opportunity, instead opting to stay on Earth with her friends and her beloved Mamoru.

In Magical Star Princess Elyon, instead of reforming the Earth, Usagi decides to head back to the Moon and rule over it as Neo-Queen Serenity. Using her Silver Crystal, she constructs a Crystal Palace where the Moon Castle stood.