In the new Ukrainian government politicians linked to the far-right have taken posts from deputy prime minister to head of defence. We profile the nationalists filling the power vacuum.
The man facing down Putin's aggression as secretary of the Ukrainian National Security and Defence Council is Andriy Parubiy. He oversees national security for the nation having previously served as security commandant during the anti-government protests in Kiev.
Parubiy was the founder of the Social National Party of Ukraine, a fascist party styled on Hitler's Nazis, with membership restricted to ethnic Ukrainians.
The Social National Party would go on to become Svoboda, the far-right nationalist party whose leader Oleh Tyahnybok was one of the three most high profile leaders of the Euromaidan protests - negotiating directly with the Yanukovych regime.
Overseeing the armed forces alongside Parubiy as the Deputy Secretary of National Security is Dmytro Yarosh, the leader of the Right Sector - a group of hardline nationalist streetfighters, who previously boasted they were ready for armed struggle to free Ukraine.
Russia has pursued a systematic, targeted policy of subjugation toward Ukraine...So of course we will prepare for a conflict with them
Dmytro Yarosh, Deputy Secretary of National Security
Inside Right Sector was an alliance of hardline nationalist groups including Patriot of Ukraine and the paramilitary group UNA-UNSO, who have fought against Russian troops in Chechnya and Moldova. Their members paraded in balaclavas and wore uniforms bearing far-right insignia, including the wolfsangel.
In 1989 he joined the moderate nationalist group People's Movement of Ukraine but from there went on to join the right wing Trizub organisation in 1994 and has been its leader since 2005, preaching and preparing for a Ukrainian "national revolution".
He told Time magazine in a recent interview: "Russia has pursued a systematic, targeted policy of subjugation toward Ukraine...So of course we will prepare for a conflict with them".
Filling the power vacuum
The new Deputy Prime Minister Oleksandr Sych is a member of the far-right Svoboda party, which the World Jewish Congress called on the EU to consider banning last year along with Greece's Golden Dawn.
The party, which has long called for a "national revolution" in Ukraine, has endured a long march from relative obscurity in the early 90s. Their declaration that Ukraine is controlled by a "Muscovite-Jewish mafia" has raised fears for the safety of the country's Jewish population.
Svoboda now controls the ecology and agricultural ministry with Andriy Mokhnyk, the deputy head of Svoboda, running ecology and Ihor Shvaika as agriculture minister.
Associate professor at Lund University Pers Anders Rudling, an expert on Ukrainian extremists, told Channel 4 News that there are other ministers who are also closely in the orbit of Svoboda.
"Two weeks ago I could never have predicted this. A neo-fascist party like Svoboda getting the deputy prime minister position is news in its own right.
"There are seven ministers with links to the extreme right now. It began with Svoboda getting 10 per cent of the vote in the last election, it is certainly a concern in the long run."
Mr Rudling warned that Europe should pay greater attention to the politics of the new regime, while warning that this in no way endorsed the actions of Russia.
"It doesn't help Ukraine to be selective and ignore this problem. Russia is using this to legitimise their unjustified aggression, I am not backing up that aggression by speaking about the rise of Svoboda."
The most important office seized by Svoboda is that of deputy prime minister, now occupied by Oleksandr Sych, whose position on abortion rights and comments about rape provoked an international outcry.
He has been criticised for declaring: "Women should lead the kind of lifestyle to avoid the risk of rape, including one from drinking alcohol and being in controversial company".
Svoboda member Oleh Makhnitsky is now acting prosecutor general.
The initial actions of the interim government have included forcing making Ukrainian the only official language of the nation and making moves to remove a law which forbids "excusing the crimes of fascism".
The anti-Russian far-right in Ukraine strongly associate themselves with the legacy of Stepan Bandera and the Ukrainian Insurgent Army. In 2010 Viktor Yushchenko made Bandera a “hero of Ukraine”, despite charges of Nazi collaboration and ethnic cleansing by the controversial figure.
It doesn't help Ukraine to be selective and ignore this problem
Pers Anders Rudling, extremism expert
The massive gains by Svoboda come ahead of the European elections that are expected to see Hungary's Jobbik and the French National Front make large advances.
However, Svoboda have been given the cold shoulder by their former European comrades with Jobbik calling for autonomy for the Hungarian minority regions in Ukraine and the BNP's Nick Griffin backing Putin.
Smaller far-right groups from Scandanavia have confirmed they have been travelling to the region to offer support and learn from the "national revolution".