Say hello to the new world leaders

The year 2015 was peppered with elections that marked substantial upsets and led to seismic changes on the global political map.

CNBC takes a look at some of the major ballots that took the world by storm and crushed the old phrase "business as usual."

One of the first global electoral upsets would set the scene for a year of protests and intense bailout negotiations. Last January's ballot brought Alexis Tsipras, the leader of the left-wing, anti-austerity Syriza party, to power and put an end to a three-year coalition led by center-right New Democracy leader Antonis Samaras.

The year hasn't been easy on Tsipras, whose critics say he bent too far to the will of Greece's lenders to help secure the country's third bailout worth $95 billion. It caused party divisions and prompted snap elections in September which saw Syriza join forces with the right-wing Independent Greeks after falling just six seats short of a majority.

But Tsipras isn't out of the woods yet, with the country still bound to austerity measures that have proved controversial among the electorate.

Portugal was thrown into uncertainty when the incumbent center-right party led by Pedro Passos Coelho failed to gain an outright majority in October elections.

Coelho was both hailed and derided for championing austerity throughout his four-year term, and momentarily became the sole European leader to win re-election after overseeing a controversial sovereign bailout.

But a left-wing coalition brought down the minority conservatives only 11 days after ballots closed, ushering in a new government under socialist leader and former Lisbon Mayor Antonio Costa.

The new government has pledged to ease tax burdens, raise the minimum wage, restore government employee salaries, reverse cuts to public services and lift the country's freeze on pensions.

How Portugal — formerly a poster child for successful austerity programs — will look at the end of Costa's term is yet to be seen.

Serious corruption allegations led to the resignation of Guatemala's now former President Otto Perez Molina in September, shortly before he was arrested over claims he was part of a scheme where companies were able to bribe officials to secure low import rates.

It paved the way for Jimmy Morales, a former television comedian, whose party clinched 67 percent of the vote — the country's largest victory margin since 1999 — on the back of a wave of disenchantment and mass protests, campaigning on the slogan "Neither corrupt nor a thief."

However, the social conservative has been criticized for running on a very narrow platform and divulging little about his plans for the country once he takes over the presidency on January 14, 2016.

Controversy may still linger, though, with his party allegedly having ties to military forces that are accused of human rights violations during Guatemala's 35-year civil war.

Canada saw a surprising political turnover in October when the third-place Liberals celebrated a sweeping win with a new, young leader at its helm. It marked a backlash against Conservative leader Stephen Harper who oversaw a near-decade of pro-austerity measures, tax cuts and unyielding support for Canada's energy sector.

Justin Trudeau's win marked the first time in Canadian history that a father and son have both held the reins in parliament, following his father Pierre Trudeau who was prime minister for 15 years in the 1970s and 1980s.

The 43-year-old has made bold pledges, with plans to legalize and regulate marijuana, raise taxes for the rich, cut taxes for the middle class and boost infrastructure spending. He also made headlines with an ambitious program to settle 25,000 Syrian refugees in the country by February.

But with questions over his experience, family history and economic policies nipping at his heels, Justin Trudeau seems to have his work cut out for him in the coming term.

Former Buenos Aires mayor and pro-business candidate Mauricio Macri stunned pollsters during the first presidential ballot in October, coming out in lock-step with Daniel Scioli — the center-left candidate backed by former president Cristina Fernández de Kirchner.

Macri edged past Scioli's 48.6 percent vote share, scoring 51.3 percent of the ballot with plans to crack down on drug trafficking and corruption, and establish pro-business policies that would open the country up to further investment.

He's also suggested he might take a softer line over Britain's claim to the Falkland Islands, which could align the country much closer with Western powers.

But with the country in the depths of sovereign default, it's unlikely to be an easy road ahead for the country's first right-wing president in over a decade.

Europe felt its eastern flanks shift further to the right in November, when the conservative nationalist Law and Justice Party won the ballot with over 37 percent of the vote, forming the first single-party government since the fall of communism in 1989.

Law and Justice, which nominated Beata Szydlo as prime minister, ran on the back of promises to raise bank taxes, lower the age of retirement, take greater control of the economy and curb privatization.

It also expressed hesitation in adopting the euro, and Szydlo could eventually come to loggerheads with the EU given its strong anti-immigrant stance at a time when Europe is struggling with a ballooning refugee crisis.

Finland welcomed a former CEO to power in April after the Center party (Keskusta) won the election with over 21 percent of the vote. However, it was forced to join forces with both the Eurosceptic party known as the Finns Party and the incumbent National Coalition party.

Juha Sipila, the former chief executive of telecoms firms Solitra Oy and Elektrobit Oyj, also founded private equity and venture capital firm Fortel Invest Oy. Drawing on his business acumen, Sipila ran on promises to cut spending and freeze wages.

Despite its northern reaching borders, Finland is likely to face further hurdles on the migration front in the coming months, with a growing number of refugees trekking across Russia to bike across the border in hopes of claiming asylum. How Sipila politically maneuvers the crisis could paint its relations with the EU in 2016.

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