A boisterous, divisive opening session of the Republican National Convention ended with an important victory for Mr Donald Trump over the #NeverTrump movement, but it also highlighted the deep chasms in the party that the controversial candidate has to try to bridge.

Republican leaders had hoped the convention in Cleveland would help heal some of the wounds that emerged from the bitter primary campaign, but found themselves instead embroiled in an early battle to quell a rebellion.

More than once, the delegates on the floor broke into deafening boos and chants as pro- and anti-Trump forces faced off in a shouting contest over the passage of a procedural motion that was necessary before the convention proper could begin on Monday.

When the motion was brought up for a voice vote - where delegates shout either "aye" or "nay" from their seats - the stadium burst into a cacophony with both sides trying to out-yell each other.

Trump supporters chanted "We want Trump!" and "USA! USA!", while the anti-Trump crowd chanted "Roll-call vote!"

The hope on the part of the #NeverTrump movement was that they could get enough support to force a roll-call vote instead of a voice vote.

A roll-call vote requires recording the vote of each of the more than 2,000 delegates attending. Even if those seeking to stop Mr Trump lost that vote, it would have caused an embarrassing delay to the speeches to be broadcast during prime time and also indicate how large the opposition to him was.

Amid the chaos, the congressman chairing the proceedings, Mr Steve Womack, returned to the podium twice to take a voice vote, both times ruling that those in favour of passing the motion were in the majority.

A roll-call vote would have been forced if a majority of delegates from seven states called for it, but frantic last-minute lobbying from the Trump campaign managed to keep that number to six.

Still, sections of the crowd would launch into impromptu chants of "roll-call vote" for the rest of the afternoon, even while a mass group photo was being taken.

For Trump supporters, the infighting was an unnecessary blight on opening day.

"They were already defeated. All they wanted to do was distract and disrupt," said Ms Cynthia Love, 52, a Trump supporter who owns a wellness centre .

Still, the extraordinary scenes were emblematic of the uneasiness in the relationship between Mr Trump and so many establishment Republicans.

The day had started with Mr Trump's campaign manager Paul Manafort launching an unprovoked attack against Ohio Governor John Kasich for not attending the convention in his own state.

"He is embarrassing his party in Ohio," Mr Manafort told reporters.

The split was so evident that Pastor Mark Burns, who led a prayer in the afternoon, included a call for political unity.

"Republicans, we have got to be united because our enemy is not other Republicans - but is Hillary Clinton and the Democratic Party," he said.

There was more unity when the evening session began and the eclectic mix of invited speakers took turns addressing the crowd.

The theme of the night was "Make America Safe Again" and most speakers focused their remarks on attacking Mrs Clinton, the presumptive Democratic nominee.

Mrs Pat Smith, the mother of one of four Americans who were killed in Benghazi, Libya, during a 2012 attack on the United States diplomatic compound, gave an emotional address where she accused Mrs Clinton of lying to her about her son's death.

"I blame Hillary Clinton personally for the death of my son... She lied to me, then called me a liar," she said.

"If Hillary Clinton can't give us the truth, why should we give her the presidency?" Mrs Smith added to roars from the crowd.

Former New York mayor Rudy Giuliani also fired up the crowd with a high-energy speech about terrorism, while a host of other speakers attacked Mrs Clinton and President Barack Obama for being soft on illegal immigrants.

The evening was capped off by an appearance by Mr Trump to introduce his wife Melania for her keynote speech. With a longer speech to come from the candidate on Thursday, he kept his remarks short.

"We are going to win, we are going to win so big," he said.