Timely Heroes

"Marvel Time" in quotes Color coding: dead, retired, active, fate unknown, missing/unconcious

The Angel: Revealed as twins, one became a homeless savior, the other an evil old man. Evil one killed good one
Black Marvel: Active until mid-1940s, retired until "two years ago," died afterwards
Black Widow: One of The Twelve, Active until 1945, fate to be revealed
Blazing Skull: Active for many years under various names, inactive at various times, reactivated "one year ago"
Blue Blade: One of The Twelve, Active until 1945, fate to be revealed
Blue Diamond: inactive for many years, but reactivated "10 years ago," last seen in space
Blonde Phantom: inactive, middle aged, daughter active as Phantom Blond
Bucky: Controlled by Soviets 1945-"this year," now operating solo
Captain America: Frozen in 1945, unfrozen "15 years ago" killed this year
Captain Terror: Retired, still living
Captain Wonder: One of The Twelve, Active until 1945, fate to be revealed (no mention of sidekick Tim)
The Challenger: Active until 1945 (at least), transported to modern age
Citizen V: died during WWII (year?)
The Defender: Killed-in-Action in 1946 (no mention of sidekick Rusty)
The Destroyer: Revealed as different from Timely, active until 1951(?) reactivated recently
Dynamic Man: One of The Twelve, Active until 1945, fate to be revealed
Electro: One of The Twelve, Active until 1945, fate to be revealed
The Falcon: active in the 40s
Father Time: Active until at least 1945 (possibly an Elder of the Universe, possibly not)
Fiery Mask: One of The Twelve, Active until 1945, fate to be revealed
The Fin: Has remained active since 1942, albeit underwater
Flexo: active in the 40s
Human Top: Revealed as different from Timely, active until late 40s, died (when?)
Human Torch: Deactivated in 1949, reactivated 1953-1955(?), reactivated "5 years ago," blown up "last year"
Hurricane/Mercury: Active until early 1950s, active again in 1960s as Major Mercury, remains active under modern name of Makarri
Jack Frost: Active through 1940s, inactive for many years, found "five years ago" and frozen again
Laughing Mask/Purple Mask: One of The Twelve, Active until 1945, fate to be revealed
Major Liberty: active during the war and Captain America considered him a friend (a letter in the Western OHOTMU)
Mastermind Excello: One of The Twelve, Active until 1945, fate to be revealed
Miss Patriot: active in the 40s
Miss America: Died 1958
Mr. E: One of The Twelve, Active until 1945, fate to be revealed
Namora: Frozen in the late 50s(?), reactivated "one year ago"
The Patriot: Retired 1950, died "five years ago"
Phantom Reporter: One of The Twelve, Active until 1945, fate to be revealed
Red Raven: Disappeared "twenty years" before modern age, replaced by andriod, re-activated "two years ago"
Rockman: One of The Twelve, Active until 1945, fate to be revealed
Silver Scorpion: super-hero until late 40s, remains active as organizer, has Alzhiemers
Sub-Mariner: Active until 1955(?), fully-reactivatd "15 years ago"
Sun Girl: known to have worked with the Human Torch after WWII.
The Terror: Inactive for many years, might be active again
Thin Man: Still active, believed dead
The Thunderer/Black Avenger: Retired, still living
Toro: Captured by Koreans 1950-53(?), inactive 1953-"10 years ago" when he was killed (at age 30?!)
Venus: Still active with Agents of Atlas.
Aarkus the Vision: Active in 40s, mentioned in the modern age as still active
Whizzer: Died "10 years ago"
The Witness: One of The Twelve, Active until 1945, fate to be revealed

Heroes confirmed through the Official Handbook of the Marvel Universe (OHOTMU):

Destroyer (Keen Marlowe): mentioned in his own profile
Ka-Zar: mentioned in his own profile
Marvel Boy(s): mentioned in their own profiles
Monstro: mentioned in Ares profile
Tommy Tyme: mentioned in Merlin's profile
Victory Boys: mentioned in Germany's profile
Young Avenger: mentioned in Germany's profile
Zephyr Jones: mentioned in Sky-Island's profile

Golden Age characters now considered modern characters:

Patsy Walker: now Hellcat
Buzz Baxter: now Mad Dog
Millie the Model (and cast): still a young model, although she's been shown middle-aged and with a teenage niece

Non-Timely characters active in Marvel history

Amazing Man: Aman is connected to the Iron Fist
Blackstone the Magician: a real person who licensed his likeness to Timely
Doctor Death/Doctor Nemesis: created human torch, in Battle Axis, faked his death, later working with the X-Men
Cat-Man: Rick Jones remembered him as a fictional comic book, might be Catman or Moon Man with points on his cowl
Green Lama: Rick Jones remembered him as a fictional comic book, might be the Thunderer minus a mask
Heap: Rick Jones remembered him as a fictional comic book, mentioned as real in recent Handbooks
Fantoman: Rick Jones remembered him as a fictional comic book, might be Black Marvel but Fantoman was used by Malibu (as Gravestone) and purchased by Marvel
Fighting Yank: Rick Jones remembered him as a fictional comic book, might be Spirit of '76
Human Meteor: in Battle Axis
Miss Fury/Black Fury: a newspaper strip licensed to Timely, later used by Malibu and purchased by Marvel (might have appeared in the Twelve and Agents of Atlas, although that could have been Cat's Paw)
Spider-Queen: in Battle Axis
Strongman: in Battle Axis
Volton: in Battle Axis

Some modern characters, like Union Jack or Spitfire, are considered to be Golden Age characters, even if they first appeared in the 1960s or later.