Blue Homeland Doctrine Explainer

Blue Homeland (Mavi Vatan) is Turkey’s contemporary maritime doctrine, first articulated in 2006 by Rear Admiral Cem Gürdeniz and later formalised and operationalised by Admiral Cihat Yaycı between 2015, when he wrote about it in his book "Basic Maritime Law" and 2019, when it was acknowledged in a memorandum of understanding with Libya and operationalised in the first Blue Homeland annual navy drill of the same year. It is not international law, nor is it recognised under UNCLOS. It is a Turkish strategic interpretation of how Ankara believes its maritime rights should be defined.

The doctrine emerged from a long‑standing Turkish argument: that the dense geography of Greek islands, combined with a strict interpretation of UNCLOS, compresses Turkey’s maritime space and undermines its strategic depth. Blue Homeland reframes this as a structural problem and asserts that Turkey must adopt a more expansive maritime posture to secure energy resources, sea lanes and geopolitical influence.

Its core claims include:

• Maritime sovereignty: Turkey should control or contest maritime zones it views as unfairly restricted by island geography. This is shown by the shaded area on the map above. It covers parts of the Black Sea, the Aegean Sea and the Eastern Mediterranean Sea surrounding Turkey. According to Turkish naval planners, the total area claimed under Blue Homeland amounts to 462,000 km². Turkey presents this as its rightful maritime domain.
  

• Energy access: Offshore hydrocarbons in the Eastern Mediterranean are treated as strategic assets.
  

• Regional posture: Turkey believes that it should project naval power across the Aegean, Eastern Mediterranean and Black Sea.
  

Highly contested:

However, Turkey's claim is highly contested. The Blue Homeland map extends into waters that Greece considers its own, by virtue of Greek islands lying inside the boundaries Turkey draws. Greece argues that islands generate full maritime zones under UNCLOS; Turkey argues that the Aegean’s geography makes "full effect" UNCLOS boundaries unworkable and that "equitable adjustment" is required. The result is a fundamental disagreement over how maritime space should be allocated. The map above represents Turkey’s interpretation, not an internationally agreed boundary. 

Explore: How UNCLOS Works and Why It Fails in the Aegean Sea