Sweden, while a country that was once home to the Vikings and which had a significant military history under the Vasa kings, has remained technically neutral in European and world affairs since before the Great War. On Thursday, that neutrality officially ended, as Sweden's membership in NATO has been formally approved.

Sweden on Thursday formally joined NATO as the 32nd member of the transatlantic military alliance, ending decades of post-World War II neutrality as concerns about Russian aggression in Europe have spiked following Russia’s 2022 invasion of Ukraine.

Swedish Prime Minister Ulf Kristersson and Secretary of State Antony Blinken presided at a ceremony in which Sweden’s “instrument of accession” to the alliance was officially deposited at the State Department.

“This is a historic moment for Sweden. It’s historic for the alliance. It’s history for the transatlantic relationship,” Blinken said. “Our NATO alliance is now stronger, larger than it’s ever been.”

Kristersson wrote in a social media post that “we are therefore a safer country.”

Sweden's membership comes close on the heels of Finland's joining the North Atlantic organization, breaking a tradition of neutrality for that Scandinavian nation as well. Sweden's membership had been held up by two NATO nations, Hungary and Turkey; Turkey ratified Sweden's membership earlier this year, and Hungary only days ago.

Sweden will now enjoy full Article 5 protection under the North Atlantic Treaty. This comes at a time when some in Europe are concerned with increasing bellicosity on the part of Vladimir Putin's Russia, who invaded Ukraine in 2022 and who is generally thought to have greater territorial ambitions.

“Sweden’s accession makes NATO stronger, Sweden safer and the whole alliance more secure,” Stoltenberg said. He added that the move “demonstrates that NATO’s door remains open and that every nation has the right to choose its own path.”

Sweden, along with Finland, which joined NATO last year, both abandoned long-standing military neutrality that was a hallmark of the Nordic states’ Cold War foreign policy after Russia invaded Ukraine in early 2022.

Previously on RedState: Sweden Joins NATO After Hungary's Obstruction Abruptly Ends

Finland Officially Joins NATO, Ukraine Expected to Make Membership Push Next

While Sweden was officially neutral during both world wars and has maintained that neutrality through the Cold War, they still field a small but well-equipped military. The current plan for Sweden's force structure is for a force comprising volunteers alongside a reconstituted national service (conscript) system consisting of three maneuver brigades, presumably a mix of armor and mechanized infantry, by 2025.

Sweden is also a participant in the Nordic Battlegroup, consisting of 2,500 troops from Finland, Norway, Ireland, Estonia, Latvia, and Lithuania in addition to Sweden. Sweden supplies the great majority of these troops, with 1,900 Swedish military members assigned. The Nordic Battlegroup consists of one active mechanized infantry battalion with provisions to rapidly deploy supporting forces.

A quick look at a map shows that the Scandinavian nations are the crown of the North Atlantic; in any modern battle for the vital Atlantic trade routes, the Scandinavian world would almost certainly not have their earlier luxury of neutrality.