Once consigned to the fringes of the political scene, these parties now legitimately stand front and center alongside their more traditional counterparts.
Here's a look at the key European countries facing a political overhaul -- and how they got there.
Italy is well-known for its fluid political spectrum, having seen a number of populist parties come and go over the years.
The revolving door swung against current Prime Minister Matteo Renzi Sunday, when voters rejected his proposed changes to the country's constitution.
He had promised they'd help revive Italy's flagging economy, but voters used the opportunity to push him out, setting the scene for a general election.
The parties who stand to gain most from the shift are far-right group Northern League and the radically populist Five Star Movement, led by Italian comedian Beppe Grillo
Experts say that if Grillo comes to power, he'll likely follow through on promises to call a referendum to scrap the euro, reintroduce the Italian lira, and perhaps even follow Britain out of the European Union.
Austria looked at electing the EU's first far-right head of state since the Second World War
when it picked its next president on the same day as Italy's critical constitutional reforms ballot.
of the Freedom Party of Austria (FPO) had ridden a
populist wave to challenge for
presidential power (albeit in a largely ceremonial role). The race had appeared close, but on Sunday Hofer conceded to left-wing independent Alexander Van der Bellen
when early returns ran against him.
The far-right refugee-blocking candidate campaigned hard on the issue of migrants, calling for a complete end to immigration in a bid to preserve the country's "ethnic culture."
The migrant crisis
reached a tipping point for many in 2015 when almost a million refugees crossed into Europe from the Balkans. At least 700,000 of them traveled via Austria.
Although the country has largely been a transit stop in the migrant journey, Austria received over 88,000 asylum applications
The popularity of France's National Front has soared in the wake of terrorist attacks and an influx of refugees fleeing Middle East unrest.
Marine Le Pen, leader since 2011, has tried to "detoxify" the party founded by her father Jean-Marie of its reputation for racism and xenophobia -- and has seen its share of the vote rise to 27% in last year's regional elections.
In a recent interview with CNN
, Le Pen said that her party can cure France's economic malaise; since the 2008 economic crisis unemployment has risen from 7.1% to around 10%, while almost a quarter of the nation's youth is now out of work.
Economic growth in France, the eurozone's second-largest economy, has also slowed in recent months to just 0.2% of GDP.
Le Pen is hoping that the recent rise in populist parties and politicians around Europe and the United States will continue in April and May 2017 when French voters go to the polls to elect a new president.
The National Front leader has utilized similar tactics to the US President-elect by tapping into frustrations of the French electorate and focusing on a more nationalistic agenda to sway voters to her corner. This week she vowed to oversee a return to France's glory days, saying if she were in power, the country would be "nothing like you have seen in the last 30 years."
The United Kingdom Independence Party (UKIP) enjoyed a surge of support at the 2015 general election under the leadership of Nigel Farage.
Farage was one of the chief architects of the Brexit
campaign for Britain to leave the European Union.
UKIP's share of the vote was 12.6% behind the traditionally dominant Conservative and Labour parties.
The party finished second in 118 of the 650 parliamentary contests
. However, it only gained one seat in the House of Commons because of the UK's first-past-the-post system.
UKIP's personal record of 3,881,099 votes came at a time when immigration into the country was at its highest rate since the turn of the century.
UKIP has become a major influence in the political scene, giving a voice to those frustrated with the perceived "Westminster elite."
But recent infighting and Farage's flirtations with the US President-elect have distracted a party which must now regroup under new leader Paul Nuttall
German Chancellor Angela Merkel took a bold step by vowing to welcome one million refugees in 2015, and in 2016, she paid for it at the ballot box.
Formed in 2013, the anti-immigrant party Alternative for Germany (AfD) was initially galvanized into action by what it saw as Merkel's bungled handling of the eurozone crisis -- specifically the multiple Greek bailouts. However, since then the party has assumed a more nationalistic platform strongly opposing the influx of migrants.
AfD contributed to defeats for Merkel's Christian Democratic Union in Berlin and her home state of Mecklenburg-Vorpommern during regional elections this year. Among the top issues for voters
: rising rents, increasing gentrification and refugees.
With national elections due
in the autumn of 2017, and following a poll
suggesting that 82% of Germans were unhappy
with her open door policy, Merkel admitted the country was not handling the influx as well as it should.
Voters in the Netherlands are set to elect a new parliament in March 2017, when the anti-Muslim, anti-immigrant Party for Freedom (PVV) hopes to build on its strong showing in the past two elections.
Its leader, the flamboyant Geert Wilders,
made his name internationally in 2008 with the provocative online film "Fitna," which juxtaposed the aftermath of terrorist attacks with verses from the Quran.
The Netherlands has a rapidly growing Muslim population -- an estimated 6%
of the total in 2010.
Wilders has run on a party manifesto focused on a so-called "de-Islamification" of the Netherlands, in which he lays out an 11-point plan
pledging, among other things, to shut down all the country's Islamic schools and close the borders to migrants from Islamic nations.
Explore more on Europe's far-right movements