South Sudan's sovereignty officially breaks Africa's largest nation into two.
It is the result of a January referendum overwhelmingly approved by South Sudan voters.
The referendum was part of a 2005 peace deal that ended decades of civil war pitting a government dominated by Arab Muslims in the north against black Christians and animists in the south. The war killed about 2 million people.
Amid the independence celebrations, some residents paid tribute to relatives killed in the war.
"It is very emotional. I'm excited, but I'm also thinking of all the people who died for this to happen," said Victoria Bol, who lost dozens of family members.
South Sudan starts out as one of the poorest nations in the world, with infrastructure problems, illiteracy, lingering conflicts, and a large refugee population. There is nowhere to go but up. Link
Learn about the new country's flag, anthem, seal, and history at the blog South Sudan Info. Link