“He would get upset, slam books on the desk if people wouldn’t listen to him or understand his point of view,” said Chera Moore, who attended elementary and junior high school with him. “He would get really mad, and the teacher would say, ‘O.K., Bradley, get out.’ ”

It was something he would hear a lot throughout his life.

After Private Manning’s parents divorced, he moved with his mother to Haverfordwest, Wales, her hometown, and began a new chapter of isolation. Haverfordwest is several times bigger than Crescent. It is also centuries older, with traditions that run much deeper. A bustling market town, it offered a pace of life that was significantly faster.

Former students at his school there, Tasker Milward, remembered Private Manning being teased for all sort of reasons. His American accent. His love of Dr Pepper. The amount of time he spent huddled before a computer.

And then, students began to suspect he was gay.

Sometimes, former classmates said, he reacted to the teasing by idly boasting about stealing other students’ girlfriends. At other times, he openly flirted with boys. Often, with only the slightest provocation, he would launch into fits of rage.

“It was probably the worst experience anybody could go through,” said Rowan John, a former classmate who was openly gay in high school. “Being different like me, or Bradley, in the middle of nowhere is like going back in time to the Dark Ages.”

But life ahead did not immediately brighten for Private Manning. After his troubled high school years, his mother sent him back to Oklahoma to live with his father and his older sister.

He was hired and quickly fired from a small software company, where his employer, Kord Campbell, recalled him as clean-cut and highly intelligent with an almost innate sense for programming, as well as the personality of a bull in a china shop. Then his father found out he was gay and kicked him out of the house, friends said. Mr. Clark, the Cambridge friend, said Private Manning told him he lived out of his car briefly while he worked in a series of minimum-wage retail jobs.