Origin

Princess Fen was born to Emperor Tha-Korr and Queen Kora in the sub-Antarctic city of Atlantis.  By the time of Namor's birth, she appears to be the sole heir to the Atlantean throne.  She had two adopted brothers, Prince Byrrah and the father of Namora.

Creation

Princess Fen was created by Bill Everett in 1939 and appeared in Namor the Sub-Mariner's first story, published a few months prior to Marvel Comics #1.

Character Evolution

Golden Age

Bill Everett portrayed Fen as the most closely resembling the air breathers of her aquatic race, called the Sub-Mariners.

Silver Age

When Stan Lee and Jack Kirby brought Namor into the Silver Age they retold his origin story.  Like the rest of the Atlanteans, Fen was given blue skin.

Modern Age

Fen mostly appeared in flash backs during the Bronze and Modern Age, until the 1990s, when she appeared to be resurrected in Namor the Sub-Mariner.

Major Story Arcs

In Love with a Human

In 1920, the Altantean city beneath the Antarctic polar cap was damaged by ice breaking charges set off by the crew of the Oracle.  Fen was sent to spy on the ship and its crew.  While learning their language and spying on the air breathers, Fen and the captain, Leonard McKenzie, fell in love.  They were soon married.

Fen stopped sending reports back to Atlantis, and Tha-Korr, fearing his daughter had been discovered and was a prisoner, sent a group of warriors led by a young Krang to rescue her.  Ignoring Fen's protests, the Atlanteans engaged the crew, shot Captain McKenzie, and dragged the princess off the ship and back to Atlantis.  Months later, she bore Leonard McKenzie's child and named him Namor, which meant Avenging Son.

Seeming Death

When Atlantis was destroyed in 1950s by Paul Destine, Fen was believed to have perished.  But she had been found by Socus who switched her body with that of Artys Gran.