Rimlands

Rimlands is a geopolitical concept designating the coastal and marginal regions encircling the Eurasian heartland. It contrasts with Halford Mackinder’s Heartland Theory, which emphasized control of Eurasia’s interior, and with purely maritime power models. The term was popularized by Nicholas Spykman in the 1940s as a refinement of Mackinder’s framework, arguing that power distributed across the rimlands would be decisive for global influence.

Geographically, the Rimland comprises the densely populated, resource-rich borderlands around the Eurasian landmass, including Western Europe, the Middle East, the Indian subcontinent, Southeast Asia, and the coastal regions of East Asia and the Black Sea littoral. The exact map varies by author, but the common thread is a belt of coastal states and maritime chokepoints that enable access to sea lanes and regional power projection.

Strategically, Rimland states can control sea lanes, ports, and energy routes, allowing them to block or balance a continental power. Through alliances, base access, and naval and air power, Rimland actors project influence across regions and deter a Heartland-based hegemon. The concept emphasizes combined sea-land power and the importance of peripheral states in global competition.

Historical influence and critiques: The Rimland concept shaped Western strategy during the Cold War, informing containment and alliance-building aimed at preventing dominance of Eurasia. Critics argue it is deterministic, maps poorly to evolving technology and non-state threats, and oversimplifies power dynamics in a multipolar world.

See also: Heartland Theory; Nicholas Spykman; Halford Mackinder; geopolitics.