The Quest of the Avatar is the quest to know and become the embodiment of the Eight Virtues, or Avatar; to prove oneself to be virtuous by nature, and to show the people of the land the way of enlightenment and virtue. Lord British writes about it:
"The Quest of the Avatar is the search for a new standard, a new vision of life for which out people may strive. We seek the person who can become a shining example of our nation and guides us from the Age of Darkness into the Age of Light."
After the foundation of Britannia, Lord British established the Eight Virtues as a way to give people some guidance on how to improve themselves. In order to find a living example for all Britannians, Lord British established the Quest of the Avatar.
The Quest was composed of several parts. The first, and most important part, was to become an embodiment or partial Avatar in each of the Eight Virtues. In order to do this, any aspiring Avatar would have to travel the land, learning about the Virtues and striving to improve in each of them. Most of the information about the Virtues could be found in the town that corresponded to each Virtue, as well as in the three keeps of the Three Principles (Empath Abbey, the Lycaeum, and Serpent's Hold). Hawkwind the Seer in Castle Britannia could see inside would-be Avatars, and tell them how they were faring on their Quest for each of the Eight Virtues.
Once Hawkwind determined that a candidate was ready in a specific Virtue, they would have to travel to the corresponding Shrine in order to achieve partial Avatarhood. The Shrines of the Eight Virtues could also be visited in order to meditate and learn how to improve oneself in each Virtue. In order to enter a Shrine, one had to carry the corresponding rune, which could usually be obtained in the town associated with that Virtue. In order to meditate and communicate with the Shrine, one also needed to know the corresponding mantra.
Lord British wanted also to ensure that his agent could protect as well as exemplify the Virtues. Thus, the three Shrines of the Principles he built on the Isle of Fire were protected with creatures and traps, so that only one that had already achieved partial Avatarhood in all Eight Virtues could access them. If someone could actually reach them, they could greatly benefit from their powers. However, while the Quest of the Avatar was just starting, the Isle of Fire sank, so this part of the Quest was rendered unaccessible for the time being.
The final test for the ones on the Quest was to enter the Great Stygian Abyss, travel to its lower levels, and reach the Codex of Ultimate Wisdom. In order to achieve this feat, several things were needed, besides partial Avatarhood in each Virtue and a strong knowledge of the Virtues: the symbols of the Three Principles, the Virtue Stones, seven companions, the Key of Three Parts, and the Word of Passage.
Lord British sent the call to the farthest reaches of Britannia, and also to other worlds and times. Many tried and met with partial success, becoming partial Avatars in one of the Virtues, but only the Stranger from Earth was able to become the Avatar. But after reaching the Codex, it told the Avatar that the Quest of the Avatar is never ending; always, the goodness and virtue of an Avatar is tested. It is an eternal struggle against the darkness in man's heart, and to prove again and again to the people of the land that they are worthy of the title, "Avatar."
- According to Ultima IX, the Guardian was created by the loss of negative energy when the Quest of the Avatar was completed. This energy needed to go somewhere, and eventually manifested in the form of a "Negative Avatar" - The Guardian: The embodiment of all the evil our hero once held within. This segment of Guardian's origin is highly controversial, as many Ultima fans feel it practically nullifies the whole purpose of the Quest of the Avatar. Ultimately, this origin came about due to several plot changes throughout the Guardian saga, many of which were the results of time constraints put on the games' release dates.