President Donald Trump was impeached by the US House of Representatives on Wednesday night, becoming only the third American chief executive to be formally charged under the Constitution’s ultimate remedy for high crimes and misdemeanours.

The historic vote split along party lines, much the way it has divided the nation, over the charges that the 45th president abused the power of his office by enlisting a foreign government to investigate a political rival ahead of the 2020 election.

Having approved that abuse of power charge by a vote of 230 for to 197 against, the House then approved the second article of the impeachment resolution – that Mr Trump obstructed Congress in its investigation – by 229 votes to 198.

The articles of impeachment, the political equivalent of an indictment, now go to the Senate for trial, most likely in January.

Mr Trump is expected to be acquitted by the Republican-led chamber, but would still then have to run for reelection carrying the enduring mark of impeachment on his purposely disruptive presidency.

READ MORE: Donald Trump on brink of impeachment as US congress prepares for historic vote 

Democrats led Wednesday night’s voting, framed in what many said was their duty to protect the Constitution and uphold the nation’s system of checks and balances.

Republicans stood by their party’s leader, who has frequently tested the bounds of civic norms. Trump called the whole affair a “witch hunt,” a “hoax” and a “sham,” and sometimes all three.

Trump ImpeachmentHouse Speaker Nancy Pelosi of Calif., announces the passage of the first article of impeachment, abuse of power, against President Donald Trump (Congress TV/AP)

Mr Trump began the historic day tweeting his anger at the proceedings, before heading for an evening rally in Battle Creek, Michigan.

As the House debated the articles of impeachment, Trump’s tweets switched to all capital letters: “SUCH ATROCIOUS LIES BY THE RADICAL LEFT, DO NOTHING DEMOCRATS. THIS IS AN ASSAULT ON AMERICA, AND AN ASSAULT ON THE REPUBLICAN PARTY!!!!” he wrote.

At the rally, a defiant Mr Trump pumped his fist before an enthusiastic crowd, boasted of “tremendous support” in the Republican Party and said: “By the way it doesn’t feel like I’m being impeached.”

House speaker Nancy Pelosi, once reluctant to lead Democrats into a partisan impeachment, now risks her majority and speakership to hold the president accountable.

What Ms Pelosi called a sad and solemn moment for the country, coming just 11 months after Democrats swept control of the House, actually unfolded in a caustic day-long session that showcased the nation’s divide.

“Today we are here to defend democracy for the people,” Ms Pelosi said as she opened debate.

The split was not just along party lines, but the cultural, regional and racial differences that underscore the partisanship in Congress. People gathered at the Capitol steps, and in protests across the nation, to follow the impeachment vote.

Trump ImpeachmentHouse Speaker Nancy Pelosi of Calif. arrives the morning before the impeachment vote (Andrew Harnik/AP)

The impeachment resolution stated: “President Trump used the powers of the Presidency in a manner that compromised the national security of the United States and undermined the integrity of the United States democratic process.”

The resolution said the president “betrayed the nation by abusing his high office to enlist a foreign power in corrupting democratic elections,” and that he obstructed Congress’ oversight like “no president” in US history.

READ MORE: US House of Representatives heads for vote on impeaching Donald Trump 

“President Trump, by such conduct, has demonstrated that he will remain a threat to national security and the Constitution if allowed to remain in office,” it said.

The House impeachment resolution laid out in stark terms the two articles of impeachment against Mr Trump stemming from his July phone call when he asked the Ukraine president for a “favour” — to announce it was investigating Democrats ahead of the 2020 election. He also pushed Ukrainian President Volodymyr Zelenskiy to probe unsubstantiated corruption allegations against Joe Biden, the former vice president and 2020 White House contender.

At the time, Mr Zelenskiy, a young comedian newly elected to politics, was seeking a coveted White House visit to show backing from the US ally as it confronted a hostile Russia at its border.

He was also counting on $391 million (£298 million) in military aid already approved by Congress. The White House delayed the funds, but Mr Trump released the money once Congress intervened.

Beyond the impeachments of Andrew Johnson in 1868 and Bill Clinton in 1998, this first impeachment of the 21st century is as much about what the president might do in the future as what he did in the past.

Republicans argued Democrats were impeaching Mr Trump because they knew they could not beat him in 2020.

“This vote is about one thing, and one thing only: They hate this president,” said Republican Representative Chris Stewart.

But Democrats warned the country could not wait for the next election to decide whether Mr Trump should remain in office because he had shown a pattern of behaviour, particularly toward Russia, and will try to corrupt US elections in 2020.

“The president and his men plot on,” said Democrat Adam Schiff, chairman of the Intelligence Committee that led the inquiry. “The danger persists. The risk is real.”

The outcome brings the Trump presidency to a milestone moment that has building almost from the time the New York businessman-turned-reality-TV host unexpectedly won the White House in 2016 amid questions about Russian interference in the US election – and the rise of the “resistance”.

Democrats drew from history, the country’s founders, and their own experiences, as minorities, women and some immigrants to the US, seeking to honour their oath of office to uphold the constitution.

Democrat Lou Correa spoke in Spanish asking God to unite the nation.

“In America,” said his fellow Democrat Hakeem Jeffries, “no one is above the law.”