Manafort's former longtime business partner, Rick Gates, also was charged in the 31 page indictment, made public on Monday. Gates and Manafort both surrendered to authorities on Monday morning.
The two men pleaded not guilty to all charges during a court appearance later Monday. A spokesman for Gates said the former lobbyist "welcomes the opportunity to confront these charges in court." A Manafort spokesman declined to comment.
In a statement, Special Counsel's Office spokesman Peter Carr said the indictment "contains 12 counts: conspiracy against the United States, conspiracy to launder money, unregistered agent of a foreign [government], false and misleading [foreign lobbying disclosures], false statements, and seven counts of failure to file reports of foreign bank and financial accounts. The case was unsealed today after the defendants were permitted to surrender themselves to the custody of the FBI."
Multiple law enforcement sources also told NBC News there was a statute of limitations issue in play that may have helped drive the timing of the indictments, which were handed down Friday.
Following news of the indictments, a White House source told NBC News that the charges had not come as a surprise to the Trump administration. "The White House has been saying for weeks the special counsel is moving far more quickly and deliberatively than people have been reporting. The fact that the special counsel is actively performing its duties does not come as a surprise to the White House," the source said.
The indictments mark a new phase in Special Counsel Robert Mueller's investigation into Russian attempts to interfere in the 2016 presidential election. They also cap off a year of escalating legal problems for Manafort and Gates, who worked with Manafort for years on many of his foreign lobbying contracts.
In late July, FBI agents under Mueller's direction raided Manafort's home in Alexandria, Virginia, and seized documents and other materials related to the probe. In September, the Times reported that lawyers working for Mueller told Manafort that they planned to indict him.
Manafort joined the Trump campaign as an adviser in March 2016 and was promoted to chairman three months later. At the time, he was credited with helping Trump's campaign recover from a bruising primary battle and move on to a formal nomination at the Republican National Convention in Cleveland.
While Manafort was well known in Washington circles for his controversial lobbying clients, it wasn't until August 2016 that his past work became an issue for Trump.
On Aug. 16, the Times reported the existence of a secret ledger in Ukraine that showed more than $12 million in undisclosed payments to Manafort from a one-time client, Ukraine's ousted former president, Viktor Yanukovych. Days later, Trump accepted Manafort's resignation from the campaign.
Since the inception of the probe, Trump has repeatedly dismissed Mueller's investigation as a "Russian witch hunt" and a "hoax" cooked up by Democrats unwilling to accept the 2016 election's results.
Emboldened by a Washington Post report showing that the Democratic National Committee and Hillary Clinton paid for the research for a hotly disputed dossier seeking to connect the president to Russia, Trump has insisted "there was NO collusion between Russia and Trump."
Trump has adopted a tone of defiance. However, inside the White House, nearly all of Trump's top aides, and the president himself, have hired outside lawyers to represent them in the probe — a sign of how serious the situation is for the West Wing.