The Marvelman Family were the results of a British Military research project called Zarathustra that used information gleaned from a UFO crash site to create Superhuman bodies.
The bodies were found to have no consciousness of their own, they were merely husks built in order for other Alien lifeforms to transfer to. A Nazi scientist named Gargunza was able to reverse engineer much of the alien tech, which concerned linking the body to a specified person, and the placement of the body into another dimension from where the linked person could swap his own body in and out from.
There were three unknowing subjects of this experiment all of whom were the children of deceased army personnel. Mike Moran (Marvelman), Dickie Dauntless (Young Marvelman), and Johnny Bates (Kid Marvelman), the three spent much of their early life hooked up to virtual reality machines.
The Marvelman Family were created by Mick Anglo for L Miller and Son as a replacement of the Marvel Family after Fawcett had cancelled the title due to pressure from DC Comics. L.L Miller had had a licensing deal with Fawcett to reprint their comics in the UK and the line had been very successful, so after the material dried up they decided to go it alone and create their own versions of the characters.
In the 80s The Marvel Family were brought back by Alan Moore and re-imagined in a grittier manner for the anthology comic Warrior, leading to renewed popularity and interest for the characters worldwide.