His house was demolished by mistake, his dog run over, his parents had both died when he was a little boy (their Christmas Tree fell and crushed both of them, on Christmas Day), and who had been forced to live with grandmother and work in her shoe factory most of his life. He was frequently beaten by his grandmother with her walking stick and abused by others for his appearance and child-like mental state.
However, he had the mindset that with all the bad things that happened to him then something good would happen eventually. Until one day when he missed the subway, which although he admits is insignificant, was the last straw for him. He had a fascination with the way things were put together, which informed his crimes; he would sneak out late at night to disassemble and reassemble mechanical devices which had upset him in some way. As his sole knowledge about their workings came from books borrowed from the public library, the "fixed" devices caused numerous accidents. The first was the same train he missed which then crashed.
Humpty's final crime was when he was late for a boat he was going to take to leave the city when he had been found out due to the nearby clock tower being off by an hour. This resulted in several of the various giant objects situated on Gotham's rooftops collapsing into the streets, which inspired a law banning such devices. When Batgirl tried to apprehend him for this, he fell off the rooftop. She saved him- but dislocated her arms in the process. Humpty, being far from aggressive, promptly slipped her arms back into her sockets and surrendered himself to her. Revealing that she had tracked him by his overdue library withdrawals, her sole request was why he had withdrawn a copy of Grey's anatomy. Humpty placidly took her back to his home and revealed he had killed his abusive grandmother, who he believed had to have been broken and in need of repair, hacked her apart, then attempted to sew her together again with bootlace. It was likely this crime that resulted in his being sentenced to Arkham Asylum.
After the Black Glove's failed attempt to destroy Batman, all the inmates from Arkham Asylum were transferred to Blackgate until Arkham was completely decontaminated. On their way back to Arkham, the vehicles that transported the inmates were assaulted by a new Black Mask, who freed the inmates, blew the asylum in front of all of them and forced them to join his army. Dumpler was among the inmates who joined Black Mask's group.
- Gadgetry: Dumpler has a natural knack for piecing together broken or disassembled items.
- 17 Appearances of Humphry Dumpler (New Earth)
- 9 Images featuring Humphry Dumpler (New Earth)
- 2 Quotations by or about Humphry Dumpler (New Earth)
- Character Gallery: Humphry Dumpler (New Earth)
Secret Society of Super-Villains member