Edgar was born the son of Jess Johnson and Thunder Quartermaine. By the time he was born, Thunder earned about 20 billion bucks in today's money, via building the notorious Johannes Springfield statue and of course founding New Springfield, the capital of the Springfield state. As a child, his father had frequently been abusive and drunk, which indicated that his last few years of life focused on his really fast downfall from grace.
As he grew older, he got fostered by both the Burnses and later the Quimbies. An adept architect and later drunkard treasure hunter, his designs of many old buildings in Port Charles, Springfield, New Springfield (the Capital city of the Springfield state that his father founded) and various fictitious cities including Llanview are all famed for their legacy.
He had two wives (Martha Louise Jacobs, an Iroquois and Liza Balan, a countess), a confidante friend (Alexis Pavlovich) and a mistress (Alke Duff), plus he birthed about sixteen children, including - confusingly - the first four Howard K. Duffs! That's because the name Howard K. Duff was his all time favourite. He died in 1898.