Joseph Stalin Widely considered a psychopath, Joseph Stalin is estimated to be responsible for anywhere from 20-40 million deaths total. Coming from a troubled childhood, he ruled Russia with an iron fist during the Red Terror.

Osama bin Laden Bin Laden is known for founding al-Qaeda, the militant organization that claimed responsibility for the September 11 attacks on the United States, in addition to many other mass-casualty attacks against civilian and military targets.

Heinrich Himmler The commander of the SS Schutzstaffel and head of the concentration camps, Himmler was the mastermind who gassed inmates with toxic poison in chambers and systematically worked and starved them to death.Responsible for the genocide of millions, Himmler committed suicide in 1945.

Ted Bundy The most infamous serial killer of all time, Theodore Robert Bundy is estimated to have killed anywhere from 40 to 100 women in unspeakably gruesome ways. It's heartbreaking to know the future that awaits this seemingly normal child.

Charles Manson Manson is a murderer and conspiracist who ordered his commune members to murder rich people in Beverly Hills. He's still in prison to this day

John Wayne Gacy, Jr. Nicknamed the Killer Clown, Gacy was an American serial killer and rapist who was convicted of the sexual assault and murder of at least 33 teenage boys and young men in a series of killings committed between 1972 and 1978 in Chicago.

Jeffrey Dahmer Dahmer was an American serial killer and sex offender, who committed the rape, murder and dismemberment of 17 men and boys between 1978 and 1991. Many of his later murders also involved cannibalism to some extent.Dahmer was beat to death in prison, but his childhood photo is chilling to look at.

Saddam Hussein The fifth President of Iraq was largely condemned throughout the world for the brutality of his dictatorship. He was executed after being convicted of charges related to the killings of 148 Iraqi Shi'ites.

Emperor Hirohito Hirohito served as Emperor of Japan from 1926 to 1989, but is most remembered for the 1937 war crime called The Rape of Nanking (then the capital of China, now known as Nanjing). During the occupation of Nanjing, the Japanese army committed many atrocities, such as rape, looting, arson and the execution of prisoners of war and civilians.The death toll is estimated to be around 300,000.

Alexander Pichushkin Known as “the Chessboard Killer,” Pichushkin murdered nearly 50 elderly homeless men in and around Moscow, Russia. According to him, he murdered people because he was competing with another killer.

Adolf Hitler A man whose name has come to signify evil in all its capacities, Hitler is probably the most infamous and evil person in all of human history. He directly caused the death of millions of innocent Jews, gypsies, homosexuals and people with mental and physical illness, not to mention the millions of other lives lost in World War II as an indirect result of his actions.

Albert DeSalvo Between June 14, 1962 and January 4, 1964, DeSalvo killed between 13 women in the Boston area. Pictured here on the left, it's hard to believe he would grow up to be a serial killer.

Gary Rigway Known as the Green River Killer, Rigway was a serial killer convicted of 48 separate murders who later confessed to nearly twice that number. His childhood picture is nothing but innocent, however.