So much for the easy stuff. Now comes the hard part as the rookie prime minister and his team confront the reality of delivering on Trudeau's promises of "real change."
Here are 10 of the biggest challenges ahead in the year to come.
1. The budget.
Finance Minister Bill Morneau is expected to table his maiden budget in February or March. He's got the unenviable task of trying to deliver all the Liberals' pricey campaign promises without plunging the country deeply into deficit.
Trudeau promised during last fall's election campaign that a Liberal government would run "modest" deficits of less than $10 billion in each of the first three years before finishing up the final year of his mandate with a slim surplus of $1 billion.
But parliamentary budget officer Jean-Denis Frechette has estimated that over the medium term, the government could run up deficits $10.8 billion higher than Morneau has projected — and that's before factoring in all the new spending the Liberals have promised. Morneau acknowledges the books are in worse shape than anticipated, as commodity prices continue to plummet and economic growth remains stalled.
Little wonder Trudeau's promise to run modest deficits has already been downgraded to a "goal." Trudeau says he's still firmly committed to producing a balanced budget in the fourth year but the bigger the deficits amassed in the first three, the harder it will be to achieve balance.
2. Withdrawing Canadian fighter jets from the U.S.-led bombing campaign in Syria and Iraq.
Trudeau has promised to end Canadian participation in the air war but says Canada will continue to contribute in some other way to the campaign against Islamic radicals. He's talked about using Canadian troops to help train local military and police but how many and how close to the front lines the trainers may be has yet to be determined. The government is also talking to NATO allies about other ways Canada could contribute.
CF-18 Hornet in the Abbotsford International Airshow at Abbotsford Airport, British Columbia, Canada on Friday, Aug. 9, 2013. (Photo: CP)
Canada's commitment to the current air mission ends on March 31.
3. Resettling 10,000 Syrian refugees by the end of 2015 and another 15,000 by the end of February — two months later than originally promised.
Fewer than 4,000 have arrived so far, but the Liberals insist the remainder will come by the government's self-imposed deadline. The logistics of processing and moving so many people has proved much more complicated and costly than anticipated.
4. Meeting with premiers and territorial leaders by mid-March to hammer out a detailed national climate change strategy.
Having agreed to an ambitious 195-country deal to limit global warming to 2 degrees Celsius above pre-industrial levels, Trudeau and the premiers now have to set a specific target for reducing Canada's greenhouse gas emissions and figure out how to achieve it.
Saskatchewan Premier Brad Wall (Photo: CP)
The strategy will involve putting a price on carbon and will require consensus among the premiers, which may be hard to come by. Saskatchewan Premier Brad Wall has already signalled his concern that imposing a price on carbon will unfairly damage the economies of energy producing western provinces, already reeling from the plunge in oil prices.
The previous Conservative government set a target to cut emissions by 30 per cent below 2005 levels by 2030. The Trudeau government has said that target is a "floor;" it hopes to set a more ambitious goal.
5. Develop a nation-to-nation relationship with indigenous peoples and work in partnership to improve housing, infrastructure, health care, child welfare, education and community policing, as promised in the campaign.
That includes immediately setting up a national inquiry into missing and murdered indigenous women, delivering on all 94 of the Truth and Reconciliation commission's recommendations and ending all boil-water advisories on reserves within five years.
Any one of those promises would be ambitious. Taken together, they're daunting.
6. Pass a new law that recognizes the right of clearly consenting adults who are enduring intolerable physical or mental suffering to seek medical help in ending their lives.
The Supreme Court, which struck down the prohibition on doctor-assisted dying last February, gave the government a year to draft a new law but the Trudeau government is asking for a six-month extension.
The Trudeau government has until the end of February to draft a new law on doctor-assisted dying. (Photo: CP)
The government has struck a special joint parliamentary committee to consult widely and report back with recommendations for a new law by the end of February. Assuming the court grants the extension, the government aims to have a new law in place by the time Parliament breaks in June for the summer.
7. Fill 22 vacancies in the scandal-plagued Senate.
The government has announced the creation of an arm's-length advisory board to recommend non-partisan nominees for appointment to the Senate, a move Trudeau says is aimed at restoring the maligned upper house to its intended role as an independent chamber of sober second thought.
The five-member board is supposed to recommend nominees to fill five vacancies by early next year, with the rest to follow by the end of 2016.
Trudeau has touted the new process as the only practical way to achieve concrete changes in the Senate without getting bogged down in constitutional negotiations. The success of his approach will be judged in large measure by the quality of senators he eventually appoints.
8. Deliver on Trudeau's promise that the 2015 election will be the last under the first-past-the-post electoral system.
He's pledged to create an all-party committee to consult on alternatives — including ranked ballots, proportional representation, online voting and mandatory voting — and report back within 18 months.
The Liberals maintain that electoral reform should be the product of all-party consensus but, with each party looking out for its own self-interest, that may prove impossible.
Even before special committee is struck, Trudeau is facing opposition accusations that he favours a ranked ballot system because it would theoretically benefit his centrist party most. And he's under pressure from the Conservatives to commit to holding a referendum on whatever is ultimately proposed, a process that has killed electoral reform initiatives in three provinces and could do the same for any federal proposal.
9. Legalize, regulate and restrict access to marijuana.
This will be a complex and controversial file that will require working with the provinces. If Trudeau wants to achieve legalization during his first mandate, the government will have to get down to work quickly in the new year.
Marijuana legalization is one of the challenges Trudeau's government will face in 2016. (Photo: CP/Getty Images)
10. Repeal parts of the previous Conservative government's controversial anti-terrorism act and introduce new legislation that better protects rights and freedoms while improving security.
Among other things, Trudeau has promised to create an all-party parliamentary committee to oversee national security agencies, narrow the definition of terrorist propaganda and ensure lawful protests and advocacy are not considered terrorism.
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