Chelsea Manning was originally sentenced to 35 years in jail, but had her sentence commuted as Barack Obama left office
Chelsea Manning walked out of military prison on Wednesday, seven years after being arrested for passing secrets to WikiLeaks in the largest breach of classified information in US history.
Manning, 29, was released from the US Disciplinary Barracks at Fort Leavenworth, Kansas, at about 2am, according to a brief statement released by the US Army.
The former military intelligence analyst, then known as Private First Class Bradley Manning, was convicted of providing more than 700,000 documents, videos, diplomatic cables and battlefield accounts to WikiLeaks, the international group that publishes such information from anonymous sources.
"After another anxious four months of waiting, the day has finally arrived. I am looking forward to so much!" said Manning in a statement released by her legal team.
She posted a picture on Twitter of her black-and-white Converse baseball shoes with the caption "First steps of freedom!!" followed by a smiley-face emoticon. She later posted an image of takeaway pizza.
"Whatever is ahead of me, is far more important than the past," said Manning, whose original release date was set for 2045. "I'm figuring things out right now -- which is exciting, awkward, fun, and all new for me."
Manning twice attempted suicide in jail, the second time in an isolation cell where she had been sent as punishment for the first attempt.
Manning was arrested in July 2010 over the release of a huge trove of more than 700,000 classified military and diplomatic documents via WikiLeaks.
Manning said in 2014 that she chose to disclose the classified information to expose truths about the war in Iraq "out of a love for my country."
Before he left office, then president Barack Obama commuted the final 28 years of Manning's 35-year sentence. The decision angered national security experts who say Manning put US lives at risk, but it won praise from transgender advocates who have embraced her transition to a female gender identity.
After her arrest in 2010 Private Manning was ultimately charged with 22 offences, including having "wantonly [caused] to be published on the internet intelligence belonging to the US government, having knowledge that intelligence published on the internet is accessible to the enemy,” an offence that could have potentially provoked the death penalty.
Manning has struggled to cope as a transgender woman in the Fort Leavenworth, Kansas, men's military prison, accepted responsibility for leaking the material.
— Chelsea Manning (@xychelsea) May 17, 2017
Lauded as a hero by freedom of speech advocates and as a traitor by others, including President Donald Trump, Manning is expected to head to Maryland, where she lived with an aunt before joining the army as a young man.
"It's going to be a profound change for her," Evan Greer, a friend of Manning, told AFP.
"She has been incarcerated for more than seven years and held in conditions that the United Nations considers to be torture. She's been through a tremendous amount."
"Understandably she has a lot of question marks about what her life is going to be like next, but it's also her first chance in her adult life that she is really going to be able to define that for herself," Greer said, noting that Manning joined the army at a very young age.
Among the hundreds of thousands of documents released by Manning to WikiLeaks was the now infamous “collateral murder” video which appeared to show gunsight footage from a US Apache helicopter as it fired upon a group of Iraqi men, killing as many as 18 people including two correspondents from Reuters.