WASHINGTON — Most Americans probably had never heard of George Papadopoulos until Monday, when it was disclosed that he pleaded guilty Oct. 5 to lying to federal investigators looking into possible Russian intervention in last year’s presidential election.

So who is George Papadopoulos?

He’s a 30-year-old, self-described oil, gas and policy consultant who served as a foreign policy adviser to Donald Trump’s presidential campaign. Before joining the Trump team, Papadopoulos was an adviser to Ben Carson’s campaign for president.

Trump identified Papadopoulos as one of his advisers in a March 2016 meeting with The Washington Post editorial board, during which he described Papadopoulos as “an energy consultant. Excellent guy.”

Papadopoulos includes that endorsement from Trump at the top of his LinkedIn page. He also notes that Carson, now Trump’s secretary of Housing and Urban Development, called him “a distinguished individual.”

Papadopoulos claims on his LinkedIn page that he has participated in business, policy and oil and gas conferences in the United States, Europe and the Middle East. He says the State Department nominated him as "a top five finalist" to represent the United States in 2011 at the emerging leaders UNESCO forum in Paris.

Papadopoulos graduated from Niles West High School in Skokie, Ill., in 2005, and earned a bachelor’s degree in political science and government from DePaul University in 2009. During his Oct. 5 arraignment and plea hearing, Papadopoulos said he was born in Chicago and indicated that he still lives there.

He went on to earn a master’s degree in 2010 from the University of London, where his dissertation focused on “the deleterious effects of low governance and state capacity levels” in the Middle East. Later, he was accepted into the London School of Economics, where he worked on a second master’s degree in international political economy.

He says he speaks Arabic, English, French and Greek and worked for four years as a research assistant to the Hudson Institute, a conservative think tank based in Washington.

The Hudson Institute, however, said in a statement Monday that its records show that Papadopoulos started there as an unpaid intern in 2011 and provided research assistance on a contractual basis to one of its senior fellows.

“Mr. Papadopoulos was never a salaried employee of Hudson Institute, we have had no relationship with him since 2014, and it would be inappropriate for us to comment on legal proceedings of which we have no knowledge and to which we are not a party,” the statement said.

According to court records released Monday, Papadopoulos pleaded guilty to lying to federal investigators about his interactions with several Russians who had high-level connections to the Kremlin. Papadopoulos admitted having contacts with a Russian who promised "dirt" on then-candidate Hillary Clinton in the form of "thousands of emails," and urging campaign officials to meet with Russian officials.

Also Monday, special prosecutor Robert Mueller filed criminal charges against Trump campaign officials Paul Manafort and Rick Gates, alleging that they hid millions of dollars they were paid by pro-Russian Ukrainian groups for lobbying efforts prior to joining the Trump campaign

Read more:

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