Julian Assange has been holed up in a room in London for years after being given refuge by Equador in their London embassy building. In 2010, he was charged with sex crimes in Sweden -- a couple of women he was involved with at the time made complaints not long after Wikileaks published video and other documents of American military activities in the Middle East -- and Assange fled to England. British courts in 2012 ruled Assange should be given up to Sweden, and Assange violated his bail to flee to the embassy.
He has lived indoors since then, only making public appearances from a balcony or via the internet.
The case has been repeatedly reviewed by Swedish courts, and now they have found that in the interests of proportionality it is not worth continuing. Essentially, authorities made the decision because all legal options had been exhausted and because the prosecutor wasn't working harder to pursue the matter.
The Swedish public prosecutor wrote in a statement, "In view of this, and that to continue with legal proceedings would require Julian Assange's personal appearance in court, there is no longer any reason to continue with the investigation."
The validity of the charges have always been questioned. There have been claims the charges were politically motivated because the U.S. government was very upset with the recent leaks.
The women in question are ones who each met Assange at conferences he was a speaker at and had consensual sex. Later on, the two women discussed Assange, and afterwards laid charges for forms of non-consensual sex (alleged to have happened in addition to the consensual sex). One of the charges was molestation, one was for unlawful coercion, and one was rape, according to Swedish law (the alleged acts had to do with not wearing condoms although the woman said he must and sex while the partner was sleeping). Originally, Swedish prosecutors didn't think there was evidence of rape and that the molestation charge would still go forward but it wasn't serious enough for a warrant. The lawyer for the 2 women made an appeal to a special department and after police interviewed Assange, the director of prosecution reopened the case for rape.
Over time, the molestation and unlawful coersion charge was dropped because Swedish authorities ran out of time to question Assange, and the UN found Assange was being arbitrarily detained and should be compensated for "deprivation of liberty." The rape charge was the only one remaining until now, although Assange may still be found in contempt of court for violating his bail and fleeing.
British authorities have said Assange will be arrested if he leaves the embassy. The expectation is that he would then be extradited to the U.S.