Northern Viking Exercise Highlights 75 Years of U.S.-Iceland Defense Partnership

U.S. service members arrived in Keflavik, Iceland, in August 2026 to participate in Exercise Northern Viking 2026 alongside the Icelandic Coast Guard and other NATO allies, marking 75 years of formal defense cooperation between Washington and Reykjavik according to a Department of Defense announcement ¹. The exercise, organized by U.S. 6th Fleet, continues a series that has become a cornerstone of allied readiness on NATO's northern flank, where the North Atlantic meets the Arctic. While the DoD release provides limited operational detail, the milestone invites examination of how a small island nation without a standing army has maintained a defense relationship with the United States that spans from the Second World War through the Cold War and into the current era of renewed great-power competition.

Iceland's strategic geography has long made it a linchpin of transatlantic security. Situated astride the GIUK gap — the Greenland-Iceland-United Kingdom corridor that Soviet submarines would have needed to traverse to reach the open Atlantic — the island hosted a significant U.S. military presence at Naval Air Station Keflavik throughout the Cold War. Although the permanent U.S. base closed in 2006, the defense relationship persisted through a bilateral agreement and Iceland's continued membership in NATO, which it joined as a founding member in 1949 despite maintaining no standing military forces. The Icelandic Coast Guard serves as the nation's primary maritime security and search-and-rescue organization, operating patrol vessels and aircraft that regularly participate in allied exercises. Its integration into Northern Viking reflects a model of defense contribution tailored to Iceland's capabilities and legal constraints.

The Northern Viking exercise series itself has evolved alongside the shifting security environment. Originally focused on anti-submarine warfare and air defense during the Cold War, the drills have adapted to address a broader spectrum of maritime security challenges, including search and rescue, disaster response, and domain awareness in the High North. The involvement of U.S. 6th Fleet — normally headquartered in Naples, Italy, with responsibility for Europe and Africa — signals the naval dimension of the exercise and the importance the U.S. Navy places on maintaining operational familiarity with the North Atlantic's demanding environment. For 6th Fleet, operating in the waters around Iceland provides training in conditions that differ markedly from the Mediterranean, including harsher weather, different bathymetry, and the operational complexities of the Arctic fringe.

The 2026 iteration occurs against a backdrop of heightened strategic attention to the Arctic and North Atlantic. Russian naval activity in the region has increased in recent years, including submarine patrols and surface deployments that test NATO's monitoring and response capabilities. At the same time, melting sea ice is opening new maritime routes and resource opportunities, drawing interest from non-Arctic states including China, which has declared itself a "near-Arctic state" and invested in polar research and infrastructure. NATO's 2022 Strategic Concept explicitly identifies the High North as a region of growing strategic importance, and exercises like Northern Viking serve as the practical mechanism through which the alliance maintains the interoperability and readiness that deterrence requires.

For the Icelandic Coast Guard, participation in Northern Viking offers a rare opportunity to operate alongside advanced U.S. and NATO assets, including maritime patrol aircraft, surface combatants, and undersea warfare capabilities that Iceland itself does not possess. This interoperability is not merely symbolic; in a crisis, the Coast Guard would likely be the first Icelandic entity to engage with allied forces arriving to reinforce the island's defense. Regular exercises ensure that communications procedures, data-sharing protocols, and tactical coordination function under realistic conditions. The Coast Guard's offshore patrol vessels, such as the Thor-class ships, are designed for the North Atlantic's rough seas and can contribute to the alliance's maritime domain awareness picture even in the absence of larger Icelandic naval forces.

The exercise also illustrates the burden-sharing dynamics within NATO. Iceland's defense contribution has historically taken the form of hosting infrastructure — most notably the Keflavik airfield, which remains available for allied use — and providing the Coast Guard's specialized capabilities rather than fielding conventional military units. This arrangement has sometimes drawn scrutiny from allies who argue for more equitable defense spending, but it also reflects a pragmatic division of labor: Iceland provides geography and maritime expertise, while the United States and other allies provide the combat capabilities that would be disproportionately expensive for a population of roughly 380,000 to maintain. The 75-year milestone suggests this bargain has proven durable across multiple strategic eras.

From the American perspective, the longevity of the relationship underscores the value placed on Iceland's geographic position. During the Second World War, U.S. forces occupied the island in 1941 — before American entry into the war — to preempt a potential German move and secure the North Atlantic convoy routes. That occupation laid the foundation for the 1951 bilateral defense agreement that formalized the U.S. military presence. Throughout the Cold War, Keflavik served as a critical node in the SOSUS underwater surveillance network and a base for P-3 Orion maritime patrol aircraft that tracked Soviet submarines. The base's closure in 2006 reflected a post-Cold War assumption of reduced threat, but the subsequent return of Russian undersea activity and the growing strategic weight of the Arctic have validated the decision to maintain the defense agreement and exercise series.

The participation of "other NATO allies" alongside the United States and Iceland, as noted in the DoD announcement, points to the multilateral character of Northern Viking. While the release does not enumerate the additional participants, previous iterations have included contributions from Canada, Denmark, Norway, France, Germany, and the United Kingdom — nations with direct Arctic or North Atlantic interests. This multilateralism reinforces the principle that the defense of the northern flank is a shared alliance responsibility, not solely a bilateral U.S.-Iceland affair. It also provides a venue for allies to develop common tactics and procedures for operating in a region where environmental conditions impose unique demands on platforms, sensors, and personnel.

Looking ahead, the Northern Viking series will likely continue to adapt as the security environment evolves. The growing emphasis on undersea warfare, the proliferation of unmanned systems for maritime surveillance, and the integration of space-based assets into the maritime domain awareness picture all suggest future exercise scenarios that differ substantially from those of even a decade ago. The 75-year marker serves as a reminder that the U.S.-Iceland defense relationship has survived precisely because it has adjusted to each era's strategic realities — from convoy protection to anti-submarine warfare to the current focus on domain awareness and deterrence in a contested High North. As long as the GIUK gap remains a strategic chokepoint and the Arctic continues to open, the rationale for exercises like Northern Viking will endure.