Avatar
Is he here? Will he come? We can only guess. This is the savior of Britannia many times over. While he wasn't able to appear in time to save the Beta shard from collapse into evil and the rule of evil entities, it was thought that such an event (the summoning of the avatar to our shards) is possible. The theory is complex, but holds some merit. It is also rumored that he only returns to the "original" Shard, which none of us live on. So, we're left knowing little more than rumors.

Crawworth
The adopted son of Hartham, Trinsic's late captain of the guards. Crawworth is the sole survivor of a village that was pillaged by a band of powerful orcs. Hartham saved Crawworth's life as a child by killing the band of orcs that slew Crawworth's parents. Crawworth is a great warrior, and a man of honor.

Duryn
This is the man, the first agent of the Zog Cabal, to act. He killed Hartham with a poisoned blade, and then fled, creating a manhunt by Crawworth. Duryn was eventually captured, only to babble on about the coming doom to the land, and then swallow his own poison, killing himself.

Exodus
The child of Mondain and Minax. He was a machine being (cyborg?) who came to avenge his parents deaths in a previous Ultima. He has since been killed. Again, he's never even been mentioned in Ultima Online, but his relationship with Mondain makes him worth mentioning. (It has been suggested that this character/event is not known to our shards and thus holds no meaning to what can happen on them)

Fildan the pyrotechnist
A new man on the scene. This is a mage who supposedly loves to research magic for no reason other than the complete enjoyment of using it. It is not known what his intentions really are, but he is the creator of the "DeathTrap" game, an unknown, undocumented device that we can only hope to see and understand someday.

Finth Desryn
Finth is Trinsic's new captain of the guards. He was appointed to the position recently, after the resignation of Crawworth. Since then, he's had some run-ins with Lord Jou'Nar. Finth's wife was apparently murdered by Jou'Nar's attack on a caravan out of Scara Brae.

G'Splat
One of the two trolls that have repeatedly attempted to invade Vesper from the north. They're powerful, yet somewhat cowardly when pushed. G'Splat was recently killed in a failed attempt at complete conquering of the forests north of Vesper. On him was a book of instructions from a character known only as "LM"

G'Thunk
The "brother(?)" of G'Splat.

Guardian
Entity of unknown origin who is "hell-bent" on conquering every shard of Sosaria(now known as Britannia) and filling them with his vile evil.

Hartham
Not much is known about Trinsic's old guard trainer. He was killed by a poisoned dagger in his back recently. He was a decorated defender of Trinsic for many years, and one of the finest warriors Britannia has ever seen.

Lich Lathiari
The son of Alinae and Eulin of Maginicia, and sister to Lich Kyrnia. This character was a precocious young mage who ruined his career when he attempted to utilize darker magics with his sister to re-animate his dead mother. As an undead agent of evil now, he is rumored to work for the Zog Cabal. His powers are assumed to be great, all people coming into contact with him are warned to treat him as armed and extremely dangerous.

Lich Kyrnia
Brother to Lich Lathiari. Her powers are known to be just as powerful as her brothers. The two of them are also rumored to share an incestual relationship as they rely on each other for both research into the dark magical power, as well as help in implementing their evil plans. Again, this character is extremely powerful, and all citizens are told to run the other direction whilst hiding constantly should they encounter her.

Lord Blackthorn
Not the TV Magician. This is the close friend of Lord British and high advisor to the lord on all matters of state. This man believes that the key to ruling a land is to encourage acceptance among all forms of race and choice of lifestyle. He's a practicer of alchemy in his own laboratory. While his magic is regarded as powerful, its not known exactly how he fares when stacked against Nystul, the servant mage for Lord British.

Lord British
Ruler of Britannia. (duh) He's concerned about the land he rules, yet he believes the nature of government is to tell his people how to live their lives. This has worked well so far, for the majority of humans in the land. One has to wonder if a different philosophy would allow for the uniting of all races on Britannia under one government.

Lord Jou'Nar
The Paladin gone evil, this guy is a killing machine. He's only been seen running around with a very dark plate and bloodstained sword, whilst he slew monks at the shrine of Spirituality. As far as anyone can tell, by assumption, he's hooked himself up with the Zog Cabal, and helped them to gain armaments and supplies from the government by theft, murder and betrayal.

Minax
Mondain's apprentice and lover (ooh'la'la). In a "previous" Ultima she raised her own forces of evil to avenge her lover's death. She was eventually killed herself. She's made no appearance whatsoever in UO, but her relation to Mondain makes her worth mentioning. (It has been suggested that this character/event is not known to our shards and thus holds no meaning to what can happen on them)

Mondain, the wizard
This is boy who killed his father for a chance at immortality. Mondain slew his father for the gem of immortality, and then twisted its magic to trap all of Sosaria(Britannia) inside of it. The Avatar appeared to slay Mondain, and attempt to free Sosaria. While the death of Mondain did free Sosaria(Britannia) from the evil that was sweeping the land (if only temporarily), it did not free Sosaria(Britannia) from the Gem, instead, it split it into a thousand worlds, each identical at the first moment, but quickly falling away from each other, into their own paths, quickly afterwards.

Sage Humbolt
I guess we can assume that Britannia has a Sage workforce that this man was recruited from. It's not known exactly where he came from. He seems to be on the government payroll though, helping Lord British design ways of dealing with the evil that stalks the land.

Shadowlords
The Evil manifestations (so to speak) of the Guardian's power. Before the beta shard story, there were only three of them. During the Beta story, it is assumed that the Nystul from that shard became one as well. The original three are named Astaroth, Nosfentor, and Faulenei. It is unknown what the name of the forth one is, if there is indeed a new shadowlord.

Sherry the Mouse
Sherry is the world's inside source as to what is going on behind those castle gates of Lord British's. She sees all, while cowering in a corner of the room. Though she's published two books so far, the fable that she is indeed a mouse is thought to be childish and incorrect.

The Time Lord
Yes, he's here. Read the book "My Story", by Sherry the Mouse, or, listen to your local tillerman for a while. This is supposedly the "alter"-entity to the Guardian. Little is known about him, except that he has stated (to Lord British) his desire to protect the sanctity of Sosaria.

Zog
The only man ever known to have actually spoken a comprehensible dialogue with the wisps. The wisps foolishly trusted the man with the Apocalypse(Doomsday) spell, which he then used to wipe out all life on Sosaria (this was pre-Britannia) for a period of time. I guess the fact that this happened is proof that even superhumanly intelligent creatures can make mistakes :P Zog is dead, his bones are rumored to be the oldest bones in existence on Britannia.

Zog Cabal/Legion
These are the men we all love to hate. One appeared during Hartham's wake to warn of impending destruction and death. I suppose it could be assumed that he is their leader, but so little is known about the organization that that would only be blind assumption.They are rumored to have agents all over the land, infiltrateed into various political circles. Any association between these men, and the fabled "Zog" seem to be idle imagination at this point, for Zog has long been dead.