Bradley Manning, the US soldier convicted of leaking a trove of secret documents to the anti-secrecy website WikiLeaks, will now be legally known as Chelsea Manning, a judge has ruled.
Manning is serving a 35-year prison sentence at Fort Leavenworth in Kansas and had requested the name change after court-martial proceedings revealed the soldier's emotional turmoil over sexual identity.
Leavenworth County District Judge David King granted the request to allow Manning "to legally change her name from 'Bradley Edward Manning' to 'Chelsea Elizabeth Manning'", said a statement issued by supporters.
In the same statement, Manning praised the result.
"It's worth noting that in both mail and in-person, I've often been asked, 'Why are you changing your name?'
"The answer couldn't be simpler: because it's a far better, richer, and more honest reflection of who I am and always have been - a woman named Chelsea," Manning said.
"Hopefully today's name change, while so meaningful to me personally, can also raise awareness of the fact that we ... (transgender) people exist everywhere in America today, and that we must jump through hurdles every day just for being who we are," he said.
Manning has asked authorities for medical treatment, including hormonal replacement therapy, for her gender identity disorder. But the military maintains it does not provide for such treatment.
Manning was convicted in August 2013 on espionage charges and other offences for passing along 700,000 secret documents, including diplomatic cables and military intelligence files, to WikiLeaks in the largest-scale leak in US history.
A US Army general denied clemency to Manning last week, upholding the 35-year sentence.
