“Now we have all these resources in place, it’s important for us to do this exercise to make sure that we have the capability intended,” says Major General, Jonas Wikman, the deputy commander of Sweden’s Joint Forces Command, who has come in from Stockholm.

As well as testing the ability of different regiments to work together, the exercise is designed to send a signal to Russia that this Baltic island is defended.

“We are doing a lot of things that are not visible, that are not known,” Major General Wikman continues.

“This is something that is visible. It’s important that everybody knows that we have the capability, and the will.”

Gotland, a diamond-shaped chunk of land between the coasts of Sweden and Latvia, has long been the key to the eastern Baltic.

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In an underground fort at the island’s military museum, there is a display of British ship’s crockery dating back to the Crimean War, during which British and French navies used the northern harbour to shelter the fleet that blockaded the Baltic and starved Russia of imports.

The island was even occupied by Russian in 1808, albeit for only a few weeks, and Russian military plans obtained by Sweden during the Cold War made it clear it was a target.

Mike Winnerstig, head of security policy at the Swedish Defence Research Agency, says that when they war-game conflicts, the person playing Russia very often takes Gotland as a first move.

“If you really want to disturb transportation of troops and reinforcements to the Baltic states, having Gotland as a platform for your long-distance missiles and anti-aircraft artillery is a very good thing,” he says.

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Until quite recently, Sweden made sure the island was defended.

At the height of the Cold War, Winnerstig explains, 50,000 troops could be on the island in a matter of hours, backed up by 36 tanks.

The coastline and its harbours were defended by 25 fortified, fixed-artillery units and the entrances to the island’s harbours were filled with mines that could explode under incoming ships at the touch of a button.

Winnerstig said that by remaining outside the NATO alliance, the traditionally neutral Swedes miss out on a powerful block to any Russian attack on the island.

“If they want to do something before there is a full-scale war between NATO and Russia, as we’re not part of NATO, they could treat us as they treat Ukraine right now,” he said.

“And NATO might say, ‘we will support you, of course, tell the Russians that they’re evil, that we won’t come to your help militarily’. Then Gotland would be up for grabs.”

Rutger Bandholtz, who commanded a battery of three 120 millimetre Bofors cannons guarding Slite, the island’s eastern harbour, remembers the last time the island saw tensions similar to those of today.

A Soviet submarine ran aground in 1981 outside Sweden’s biggest naval base in Karlskrona, and Sweden feared the Soviet Union would send in warships to rescue it.

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“That was the only time we had live ammunition in our cannons,” Bandholtz remembers, as he shows me one of the 120 millimetre Bofors guns at the museum. “The prime minister said ‘keep the border’, and we did. They didn’t cross it, because they realised our guns were loaded.”

In 2005, the Gotland regiment was shut down, due, Winnerstig snorts, to “the end of the Cold War, the eternal peace and the end of history”.

The demilitarisation was reversed following Russia’s annexation of Crimea in 2014 but, four years after the Gotland Regiment was re-established, it still only numbers 300 personnel.

Lukas Rosengren, commander of one of the CV90 combat vehicles down from Boden, says that over the past fortnight his unit has been so busy patrolling, that there has been no time for socialising.

“There’s been a lot of communication through work and not so much outside, because we haven’t had any spare time yet,” he says.

With President Joe Biden continuing to warn of a “distinct possibility” Russia might invade Ukraine next month, he could be on alert for some time to come.

The Telegraph, London

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