Dinah Soar was born in the Savage Land, a tropical climate area hidden on the continent of Antarctica. It has been speculated that she is either a Savage Land mutate, a mutant, or an alien. Alternatively, she may be a member of a previously unknown race of humanoid descendants of dinosaurs. The Savage Land is home to many different races and species known nowhere else on Earth.
Dinah Soar became a superhero in Wisconsin. She answered a newspaper ad placed by Mr. Immortal and joined the Great Lakes-area superhero team that he formed. She also became Mr. Immortal's lover.
Dinah Soar's speech could was never heard by anybody around her except for Mr. Immortal. Her speech balloons were always blank. If she represents a typical member of her race (whether alien or native to the Savage Land), then presumably others of her race were capable of understanding each other.
In part because of the way her speech was typically unintelligible, and in part because she appeared in so few comic book stories before she was tragically killed by the villain Maelstrom (G.L.A.: Misassembled #1 (2005), little is known about Dinah Soar's background, religious beliefs, personality, etc.
When Dinah Soar lay dying after being hit by a fatal energy blast from Maelstrom, readers were able to read some of her dying words. Dinah Soar's last words made it clear that she had a worldview and way of thinking that is extremely different from that of her fellow Great Lakes Avengers. Indeed, her thoughts and background were clearly very different from that of any known human culture. Dinah Soar appeared to be a deeply religious and spiritually sensitive woman. She spoke of Mr. Immortal's soul and apparently had been drawn to him because she could sense his incredible destiny.