Manning attended Tasker Milward in Pembrokeshire County, in central Wales. The school required students to wear forest-green V-neck monogrammed sweatshirts.
At 15, Manning stood out as a novelty for being American, said classmate Tom Dyer, who hung out at Manning's home at least three times. The mother was quiet, he recalled, but Manning was more passionate.
"He was quite energetic, always full of ideas and had a high moral compass. He would always speak up if he thought that something was wrong without actually thinking of the consequences," said Dyer, who still lives in Pembrokeshire. "Bradley had a great sense of justice."
Though Dyer is Facebook friends with Manning, he said they have not spoken in two years. Dyer said he was taken aback to hear Manning had joined the U.S. Army.
"He did not have a build for that, you know what I mean?" Dyer told CNN.
Former Tasker student James Kirkpatrick agreed with Dyer, saying that the Army seemed an odd choice for Manning. Kirkpatrick kept in touch with Manning, saying in 2010 he had talked to the soldier as recently as six months earlier.
"He didn't mention anything about what was happening, but at the same time he did seem a bit secretive," the ex-classmate said. "He was being a bit paranoid about what we did speak about on the 'net."
Out and down
"my family is non-supportive . . . im losing my job . . . losing my career options . . . i dont have much more except for this laptop, some books, and a hell of a story." -- Washington Post, instant message allegedly from Manning to Lamo.
Manning dropped out of Tasker and moved back to America in 2005. He told Lamo that he was homeless and had drifted around the country until he landed in Potomac, Md., where his aunt took him in.
A former soldier said he met Manning during this time in a Washington nightclub, and they had a physical relationship. The man, whose identity CNN isn't releasing, said the young soldier seemed "shy, very quiet, introverted."
"Brad was very different from anybody else at the club. He didn't really look like anybody else at the club," the man told CNN. "I mean, he was very slight, physically. He just appeared really out of place and really lonely."
Their relationship evolved into a friendship, and the two frequently talked about each other's dreams and ambitions, their fears, insecurities and frustrations. Manning told him he was viciously made fun of in the military for being gay. Basic training was "difficult ... because of his sexuality," the man said.
"He had given me indication that the same type of thing that he had dealt with before, as far as verbal abuse, you know, emotional abuse, derogatory comments pertaining to his sexuality," the man told CNN.
Manning didn't recognize the treatment as discrimination, the man said.
"When it came to these things, I felt like he was frankly a little bit naive," the man said. "I didn't think he realized what was happening to him. ... I think at first he felt just terrible that people would say something like that to him, and embarrassed, obviously."
Manning was "probably more angry at the military and the whole way everything was run and that was probably why I felt like he was disgruntled towards the end," he added.
Apart from discrimination, the man said Manning had a rough go with his family. He had to leave his father's home, for unknown reasons, and became homeless. Manning drove across the country, living out of a beat-up red truck, working odd jobs, the man said.
In the Army now
After a short stint at Maryland's Montgomery College, and a pizza-delivery job for minimum wage, Manning enlisted in October 2007. He went to Fort Leonard Wood, Mo., for basic training the next year.
Things did not go smoothly.
At an Arizona base in 2008 during advance training that would turn Manning into an intelligence analyst, the young soldier was reprimanded, the military said, without elaborating on details. Wired magazine reported that Manning had been caught uploading videos on YouTube in which he talked about classified buildings.
Manning graduated advanced training and was sent to Iraq. He was given top-secret security clearance.
Manning was arrested in June 2010 in connection with the release of classified U.S. military combat video, which showed the shooting deaths of Iraqi civilians and two journalists in 2007 by a helicopter gunship.
He initially invoked the Fifth Amendment and refused to answer questions, a Pentagon official said, but in February, when he entered his guilty plea to certain charges, he spent more than an hour in court reading a statement detailing why and how he sent classified material to WikiLeaks.