And so, after much personal invective, furious opposition and ugly rhetoric that appealed to the worst impulses of the American voters, this is Donald Trump's Republican Party.
A year ago, if you had told someone that today we would all be watching, in horror, a billionaire-turned-reality TV star telling tens of millions of Americans “I am your voice”, and screaming “And we will make America great again!” into a microphone in front of giant “TRUMP” letters, they would have signed you into a large medical building with lots of people in white coats.
Cleveland was certainly one hell of a party and, now, this is the party of Trump. We are left with a man who is one election – and one deeply unpopular opponent – away from the nuclear codes.
So, how exactly did the party of Abraham Lincoln and Ronald Reagan fall into the hands of a populist, anti-trade isolationist and preening narcissist who has never served a day in public office?
Easy, but first we have to go back to 1884 – yep, 132 years ago – to understand where the party stands now.
At the party convention in Chicago that year, 30 years after the party was founded, a group of dissidents in the party challenged the nomination of Maine Republican James Blaine, a man more popularly known as "Slippery Jim" who, it is said, never saw a kickback he did not like.
Many of those Republicans voted for Democrat Grover Cleveland that year because they could not back their nominee. He won the election in a big turnout – 10 per cent higher than four years earlier.
Known as "Mugwumps", these dissident Republicans counted future president Theodore Roosevelt among their ranks and were the nucleus that went on to form a more progressive Republican Party.
Heather Cox Richardson, professor of history at Boston College and author of To Make Men Free: A History of the Republican Party uses this moment by way of comparison to where the party stands now under Trump.
“The Republican Party right now looks like it did in 1884 when it had a very similar kind of a meltdown,” said Richardson, kindly walking me through the roller-coaster history of the party.
She points out that, long before Trump, the Republican Party was “being destroyed on its own”.
The schism between conservatives and moderates that exists in the party today stems from Roosevelt's walk-out at the 1912 convention, when the party re-nominated President William Howard Taft, splitting the party's vote that year and handing victory to Democrat Woodrow Wilson.
The Great Depression and Franklin D Roosevelt’s New Deal split Republicans into those who wanted to eliminate his deep government interventions in business and social welfare and those who believed they could make them more efficient.
A small rump of people thought otherwise – that the Great Depression was caused by government not being non-interventionist enough.
That group led to the conservative movement and found voice in powerful spokesmen from the 1950s: commentator and author William F Buckley jnr, Wisconsin senator Joseph McCarthy and Arizona senator Barry Goldwater.
Reagan’s presidency
This movement institutionalised politics, in the 1980s with Ronald Reagan in the White House and in the 1990s with Newt Gingrich in the US congress as the speaker of the House of Representatives.
Dog-whistle racism took hold and wealth was redistributed upwards through economic policies that embraced globalism and free trade.
This has spawned Trump’s “America First” populism or “Americanism” – a term that stood out in his acceptance speech on Thursday night.
The irony for the party Trump has acquired in a hostile takeover is that he is not a conservative or even a Republican. He is in the business of snake oil. He has hijacked the conservative movement’s “us versus them” division of the world and has appealed to blue-collar Republicans and former Democrats whose lives have been destroyed by the movement’s economic platform.
“What he is really is a salesman accurately reflecting a constituency that the ‘movement Conservatives’ have built since the 1950s,” said Richardson.
“We are at the cusp of a changing era in America, just which direction it changes in is up in the air.”
In Cleveland this week, retired US army lieutenant general Michael Flynn, who was briefly tipped as a possible running mate for Trump, put it in colourful terms.
“This is warfare. Look at the battles that he won. This country is sick of the political correctness, sick of the political class.
"People in the federal government have become disconnected with the people out in middle America. Donald Trump recognised that well before any of the political class did."