The United States government announced in October 2016 that Russia had hacked the Democratic National Committee and other Democratic party operations. Hacked emails had been released publicly, some of which contained embarrassing information about the Democratic Party and former Secretary of State Hillary Clinton, the party's presidential nominee. 

Initially, U.S. intelligence agencies did not suggest the Russian hack was intended to help Trump win the election. In December 2016, however, the Central Intelligence Agency told a group of U.S. Senators that Russia had intended to help Trump win the presidency. Continued investigation revealed email accounts of some Republican congressmen, GOP non-profits, and other party organizations had been hacked, but that information had not been released. 

The Washington Post quoted a senior U.S. official as saying, “It is the assessment of the intelligence community that Russia’s goal here was to favor one candidate over the other, to help Trump get elected." Read the Washington Post article.

See also Russia and Trump Relationship with Russia.

Timeline

Analysis

After leaked emails from Hillary Clinton and the Democratic National Committee were printed in the mainstream U.S. media and elsewhere, Trump invited Russian hackers to continue searching for deleted email. This is an unprecedented invitation for a foreign government to interfere in the United States political process. After 17 U.S. intelligence agencies agreed that the Russian government had sponsored hacking, Trump called the conclusion "ridiculous," an unusual repudiation of reports from intelligence agencies. He also falsely claimed that the Obama administration brought up the concern about foreign meddling in a U.S. election after Clinton's loss. He softened his tone somewhat after Republican leaders pressed for an official inquiry.

From his invitation to Russian hackers to search for Clinton's emails to his rejection of intelligence from multiple agencies and false claim that the concern was raised only after he won the election, Trump has demonstrated disregard for political norms and factual accuracy. He has sided with a foreign government over the conclusions of multiple intelligence agencies in the United States and elsewhere. 

Meanwhile, Russia has admitted being in touch with Trump's allies during the campaign, making its intent clear despite Trump's denials. 

Assessments

From The New York Times

“There shouldn’t be any doubt in anybody’s mind,” Adm. Michael S. Rogers, the director of the National Security Agency and commander of United States Cyber Command, said at a postelection conference. “This was not something that was done casually, this was not something that was done by chance, this was not a target that was selected purely arbitrarily,” he said. “This was a conscious effort by a nation-state to attempt to achieve a specific effect.” 

Trump's relationship with Vladimir Putin following the state-sanctioned cyberattack is "baffling to anyone with a functioning brainstem," according to Van Jones. Source: CNN.

From The New Yorker: The Russian economy has been crippled by 2013 sanctions, giving Putin a reason to engage in a propaganda campaign against the United States and deny the presidency to Hillary Clinton. 

From The Weeklings, Greg Olear: DAH, DONALD: RUSSIAN BLOOD MONEY AND THE FBI’S CASE AGAINST TRUMP (2017.01.24)

THIS IS AN ATTEMPT to assemble the pieces in the Trump/Russia jigsaw puzzle, to reveal the Big Picture.

My conclusions were heavily influenced by Louise Mensch‘s eye-opening January 17 essay, “Dear Mr. Putin, Let’s Play Chess.” Other sources include Seth Abramson’s “The Domestic Conspiracy That Gave Trump the Election is in Plain Sight,” which ran on the Huffington Post on the same day, and “A Brief History of the First Russo-American Cyber War,” by War Is Boring’s Bryan E. Frydenborg. The Steele dossier, the “Golden Shower” series of intelligence reports written by Christopher Steele in 2016 and subsequently released by Buzzfeed, was also a useful resource. I have exhaustively fact-checked assertions, linking to a wide range of news sources from across the political spectrum, from the Washington Post to Reuters to Breitbart.

The dramatis personae—the pile of puzzle pieces, if you will—is generally well known to most observers: Donald Trump, Vladimir Putin, Edward Snowden, Julian Assange, James Comey, Rudy Giuliani, Anthony Weiner, Huma Abedin, Hillary Clinton, Barack Obama, Blackwater founder Erik Prince, Trump attorney Michael Cohen, “ratfucker” Roger Stone, Paul Manafort, Russian moles in the NSA and the FBI’s New York field office, and an obscure Russian hacker named Yvegeny Nikulin.

This is how the pieces fit together. This is how they connect. This is what it means.

(Skipped text here)

In short, it’s about the money. Which makes sense, given Trump’s disgustingly obvious greed. The Russian oligarchs are laundering money all over creation, and Trump, with his opaque taxes and billion-dollar losses and cash business concerns, is somehow complicit in the scheme. Campaign finance, one imagines, is just the tip of the iceberg.

If he’s shown to be in debt to the Russians and the Chinese, Trump can explain that away. Fake news, he will say. So what. I won, people don’t care. Same with the Russian prostitutes. You can’t shame a man incapable of feeling shame. What is Trump afraid of? Prison. That would be the ultimate downfall for Donald Trump. The loss of his position, his social standing, his fortune, his golden throne, his access to beautiful women willing and otherwise. His Twitter account.

There is no “alternative fact” that can spin the very real possibility that Donald J. Trump will die in federal prison, alone.