Bradley Manning's Early Years

1987 Bradley Manning born

Bradley grew up in Crescent, Okla., a small farming town about 40 miles north of Oklahoma City. His father Brian worked in the IT department at Hertz, and his work would take him away from home for weeks at a time. Bradley's mother Susan, was a native of Wales, where his parents met while Brian was stationed there in the Navy. Susan, who had not learned how to drive, was often on her own in rural Oklahoma with Bradley and his older sister Casey.

At school Bradley kept to himself and didn't have many friends. He was small for his age and not very athletic, but he did well in class. After school, he'd spend much of his time alone with his computer. He excelled at the school science fair, winning the grand prize three years in a row, according to his father.

But according to friends and neighbors, the Mannings were a troubled family. "I always got the feeling that Bradley was scared of his dad," Bradley's closest friend, Jordan Davis, tells FRONTLINE.

2000 Bradley's parents divorce

Bradley's parents separated when he was 13 years old. After a bitter divorce, his mother moved out, taking Bradley with her.

According to Jordan Davis, Bradley changed after the divorce. "As soon as his dad left … he started doing his hair and he got different clothes and he did different things. He was more open, and more, I guess, himself."

Jordan also tells FRONTLINE that Bradley came out to him and another friend when he was 13. "He told me he was gay," Jordan recalls, "And I said 'OK. Whatever floats your boat man.' And that was pretty much it."

2001 Bradley moves to Wales with his mother

Bradley attended high school in his mother's native country. At school, he was seen as a computer geek. He was not openly gay at the time, but classmates say he was often teased, and they describe him as short-tempered.

2005 Bradley returns to Oklahoma

After graduating high school, Bradley called his father and said he wanted to come back to the U.S. He moved in with Brian and his second wife in Oklahoma City.

Brian describes Bradley as "spoiled rotten" and "a different person" when he returned. They argued over money and the house rules. Bradley did not get along with his new stepmother.

Shortly after returning to the U.S., Bradley told his father he was gay. Brian says the news was a "surprise" but that he told his son, "That's your decision, it's fine."

Bradley got a job at Zoto, a small software company, but coworkers described him as becoming increasingly erratic. He was fired after a heated confrontation with his boss.

March 29. 2006 Bradley leaves home after an explosive family fight

At home, tensions with his father and stepmother reached a breaking point. Brian Manning tells FRONTLINE the fight started as a discussion about following the house rules but then escalated.

FRONTLINE obtained the audio of a 911 call Bradley's stepmother made during the altercation. She claimed he had threatened her with a knife.

Listen to the 911 call »

Bradley was escorted from the house by police, but was not arrested or charged. The next day he moved out and never returned. Years later, Bradley would claim he was kicked out of the house for being gay.

2006-2007 Bradley bounces from job to job

After leaving Oklahoma City, Bradley moved to Tulsa, where he worked at a pizza parlor and a retail entertainment chain store. He then moved to Chicago, where he worked at Guitar Center. Finally he moved to his aunt's house in Maryland, where he worked at a Starbucks and Abercrombie & Fitch and attended community college.

Summer 2007 Bradley joins the Army

Brian Manning tells FRONTLINE he encouraged his son to join the Army to get a sense of structure in his life. "I said, 'Bradley, you're not really going anywhere,'" he recalls. "And I said, 'If you get into a place like the Army, you know, you're going to have three square meals a day, you're going to have a place to sleep and a roof over your head. And as long as you follow the path, it's all you have to do."

FRONTLINE will continue to report on Bradley Manning and Wikileaks -- watch for our upcoming investigation in May.