Bradley Manning, the U.S. soldier convicted of the biggest breach of classified data in the nation’s history, arrived at the courthouse at Fort Meade, Maryland on Wednesday, to learn how long he will spend in a military prison.

Manning faces up to 90 years behind bars for turning over more than 700,000 classified files, battlefield videos and diplomatic cables to the pro-transparency website, Wikileaks.

Manning was working as a low-level intelligence analyst in Baghdad several years ago when he handed over the documents, catapulting Wikileaks and its founder, Julian Assange, into the international spotlight.

In July, the judge hearing Manning’s court-martial, Colonel Denise Lind, found the 25-year-old private first class guilty of 20 criminal counts, including espionage and theft, but not of aiding the enemy, which was the most serious charge, carrying a possible sentence of life in prison.

The classified material that shocked many around the world included a 2007 gun sight video of a U.S. Apache helicopter firing at suspected insurgents in Baghdad. Among the dozen fatalities were two Reuters news staff, and WikiLeaks dubbed the footage “Collateral Murder.”

The case highlighted the difficulty of keeping secrets in the Internet age. It raised strong passions on the part of the U.S. government, which said Manning had put American lives at risk, and anti-secrecy advocates, who maintained Manning was justified in releasing the information.