Speaking in a live address from the White House Rose Garden, President Obama welcomed the lifting of "the dark shadow of tyranny" from Libya.
After hours of reports about the death of Libya's ousted leader, the President announced that "today we can definitively say the Qaddafi regime has come to an end."
"One of the world's longest-serving dictators is no more," he continued.
Obama said America had achieved its objectives, and soon the NATO mission would "come to an end."
However, he said American engagement would continue as the country transitioned towards "its first free elections." He said establishing a democracy would be "the ultimate rebuke" to Qaddafi.
Obama also sounded a note of warning for other intransigent Arab despots such as Syria's Bashar al-Assad and Yemen's Ali Abdullah Saleh, both of whom are presiding over brutal crackdowns on "Arab Spring" crowds.
"The rule of an iron fist inevitably comes to an end," Obama warned. "Those leaders who try to deny [their peoples] their dignity will not succeed."