CHARLOTTETOWN -- In the summer of 1864, less than three years before Canada became a country, a government steamship laden with politicians and Champagne set off from Quebec City on an unusual mission.

The destination was Charlottetown -- a voyage that 150 years ago took four days.

Aboard the SS Queen Victoria was a contingent of cabinet ministers from the Province of Canada. The delegation was led by three men: Reform Leader George Brown, Liberal-Conservative Leader John A. Macdonald and George-Etienne Cartier, leader of the Parti Bleu.

Their goal was to persuade politicians from the self-governing colonies of New Brunswick, Nova Scotia and Prince Edward Island to scrap a plan to form a Maritime union and instead join in the creation of a larger federation.

But the Canadians, who represented the united colonies that would later become Ontario and Quebec, faced big challenges.

When they arrived in Charlottetown harbour, few of the locals paid attention. For the first time in years, a circus had come to town and the city was shut down for the day.

As well, the Canadians had secured a last-minute invitation to the conference, which meant they were unofficial delegates to a meeting that was supposed to discuss something entirely different.

"It's true that the Canadians had barged in on what had been a meeting on Maritime union, but they were certainly welcomed by the Maritimers," says Christopher Moore, a Toronto-based historian and author of "1867: How the Fathers Made a Deal."

At a recent funding announcement in Charlottetown, Prime Minister Stephen Harper paid tribute to the pluck of Macdonald and his colleagues.

"In modern terms, you could say that he kind of crashed the conference," Harper said before he committed to spend an additional $5 million on the 150th anniversary celebrations.

"Then he commandeered the agenda -- some might say Ontario has been doing that ever since -- to secure central Canada's place in the new Confederation."

On the first full day of the Charlottetown conference, Macdonald and Cartier offered a broad outline of the Canadian proposals, including plans for a future Senate. Alexander Galt talked about finances the next day and Brown handled the constitutional file.

However, the Canadians needed more than clear plan and glittering oratory to win the day.

More importantly, they needed to make allies out of strangers.

"Many of these politicians had never met each other before," Moore says. "It was important that they learn to trust each other. ... They went for drives in the countryside, they went to dinner at country estates and they went out to the steamship that the Canadians had come down on."

And they drank Champagne -- a boatload of it.

Historian Peter Waite, an expert on the pre-Confederation era, says creating a sense of "good fellowship" among the newly acquainted delegates was key to securing an agreement in principle.

"The Canadians had a strong belief ... in the efficaciousness of good food and plenty of wine to make a party -- or a conference -- go," Waite wrote in a 1970 essay.

Describing a raucous fete aboard Queen Victoria, Waite wrote: "Champagne flowed like water, and union talk with it. The occasion took hold of everyone. Champagne and union!"

On Sept. 7, 1864, six days after the conference started, the bleary Maritime delegates offered unanimous support for the idea of Confederation.

And then came the grand ball at the P.E.I. legislature the next night, during which the parliamentary library was used as a bar and the legislative chamber became a dance floor until 1 a.m.

In a letter to his wife, George Brown wrote that the ball was followed by a meal and almost three hours of self-congratulatory speeches, "the poor girls (at the ball) being condemned to listen to it all."

"The fact that they socialized together and learned to get to know each other and develop some trust was a vitally important part of the Charlottetown meetings," Moore says.

More meetings and soirees were held in Halifax, Fredericton and Saint John, N.B., before detailed discussions on 72 formal resolutions were held in October at a conference in Quebec City, followed by another conference in London in 1866.

The London resolutions were redrafted into the British North America Act and Queen Victoria approved a bill that created the Dominion of Canada when it came into force on July 1, 1867.