Finland and Sweden Joining NATO—Everything You Need to Know

Since Russia invaded Ukraine on February 24, Finland and Sweden have considered applying for NATO membership, in what would be a major policy shift for the Nordic countries.

Russia has repeatedly warned of military escalation and even the potential deployment of nuclear weapons in the Baltic region if the two countries join the Trans-Atlantic alliance. If the countries do join NATO, it will be a political game-changer and bolster the alliance's defenses.

Here's everything you need to know about the two countries joining NATO.

Jens Stoltenberg Sweden Finaland
Since Russia invaded Ukraine on February 24, Finland and Sweden have been considering applying for NATO membership. Above, NATO Secretary-General Jens Stoltenberg speaks during a joint press with Sweden and Finland's foreign ministers after their meeting at the NATO headquarters in Brussels on January 24, 2022. John Thys/AFP/Getty

Why Have Sweden and Finland Stayed Out of NATO Historically?

When NATO was established in 1949, two years into the Cold War, Finland and Sweden did not join.

Finland shares a 1,300km (807-mile) border with Russia and gained independence from the nation in 1917. The countries have fought two wars against each other. In 1948, Finland signed an agreement of Friendship, Cooperation, and Mutual Assistance with Russia. The pact included an agreement that Finland isolate itself militarily from Western Europe. However, at the end of the Cold War in 1991, the threat from Russia toward Finland decreased and the Nordic country was able to operate more independently.

Sweden, meanwhile, has not fought a war for 200 years due to its policy of neutrality. Along with Finland, the country switched from a policy of formal neutrality to military non-alignment when it joined the European Union in 1995.

However, both have acted as key partners to NATO over the years and have shared intelligence and military drills with them—particularly as Russia's foreign policy has become more belligerent under President Vladimir Putin.

The below chart by Statista shows which European countries are currently members of NATO, and which are considering joining (Finland and Sweden).

Statista diagram
This chart by Statista shows which countries in Europe are members of NATO. Sweden and Finland are not members but are considering joining the U.S.-led alliance. Statista

Why Are Sweden and Finland Moving to Join NATO Now?

The war in Ukraine has killed thousands and displaced millions. Rising security concerns in Europe and fears that the conflict could spill over to other countries have pushed Finland and Sweden into seeking NATO membership.

Members of the alliance benefit from Article 5, which guarantees that an attack on one NATO ally is an attack on all.

What Do Polls Say on NATO Membership Within Sweden and Finland?

Although NATO membership is still a divisive subject, a growing number of people in both countries are warming to the idea. A survey carried out by the polling instate Novus in mid-April showed that 51 percent of Swedes were in favor of joining the western military alliance. It was the first time the pollster had recorded a majority on this issue.

According to another poll by Novus from April 2014, a month after Russia annexed Ukraine's Eastern Crimea region, 36 percent of Swedes said that their country should not join NATO.

This May, barely two months into the Russian invasion of Ukraine, only 25 percent of Swedes believed that the country should not join NATO while 48 percent said they would join the alliance.

The below graphic by Statista shows how the Swedish view on applying for NATO membership has changed over the years.

Sweden's view on NATO membership
This graphic by Statista shows how the Swedish view on applying for NATO membership has changed down the years. Statista

A poll released in March by Eva found that some 60 percent of Finns would support Finland joining NATO, an increase of 34 percentage points compared to a similar poll carried out in autumn 2021. Only 19 percent of respondents in the most recent poll would be against Finland joining NATO.

Another recent poll by private Finnish broadcaster MTV found that 68 percent of Finns are in favor of joining, while only 12 percent are against it.

Swedish foreign minister Ann Linde told Swedish television on Sunday that she believes Finland will almost certainly apply for membership. Pekka Haavisto, Finland's Foreign Minister, said two days prior that he hoped Finland and Sweden would make similar decisions on NATO at the same time.

What Has Russia Said and How Might They React?

Russia has said that there would be "serious political consequences" if the two countries joined NATO.

On February 25, a day after Russia launched the invasion, Russian foreign ministry spokeswoman Maria Zakharova warned of "serious military-political repercussions" should Finland and Sweden join.

On April 11, the Kremlin warned that if the two Nordic states join the alliance, it "will not bring stability" to Europe.

Moscow has said it would boost its forces in the Baltic Sea region if the two countries apply, and it has even raised the possibility of deploying nuclear weapons in the area in response to the two countries joining NATO.

How Soon Can NATO Membership Happen?

It could happen within a matter of weeks, with both countries becoming NATO members as soon as this summer.

On May 12, Finland will decide to apply for NATO membership, the Iltalehi newspaper reported on May 1, citing anonymous Finnish government sources. President Sauli Niinisto and Finland's parliamentary groups will need to approve the application in two stages.

In Sweden meanwhile, parliament is already conducting a security policy review, including weighing up the pros and cons of joining NATO. The results of the review are due on May 13. In tandem, the ruling Social Democrats are having an internal debate on May 9-12 on NATO membership with the party leadership due to make a decision by May 24 at the latest.

If Finland or Sweden applies, the other will likely follow, as the other Nordic countries—Denmark, Iceland, and Norway—are all founding NATO members.

However, there are concerns from the two countries that there might be an insecure "gray period" after applying, in the time before full membership comes into effect.

Both countries may ask for security guarantees to protect them from Russian aggression to be made upon application.

NATO Secretary-General Jens Stoltenberg said that he was sure that arrangements could be made for the interim period and that both countries could join "quickly."

However, ratification can take four months to a year, as parliaments of all NATO countries need to approve the new members.