The 1945 Potsdam Agreement established a new border between Poland and Germany at the so-called “Oder-Neisse line,” but it left unsettled the question of the maritime boundary on the Baltic Sea. Until 1989, the water border remained a matter of dispute between the German Democratic Republic and the Polish People's Republic socialist allies otherwise at pains to demonstrate unity in geopolitical matters—especially with regard to their shared “border of peace and friendship.” In the intervening decades, East German fishermen and Polish ship captains repeatedly ran afoul of the invisible water border, the importance of which increased as UN conventions on the Law of the Sea affected fishing, shipping, drilling, and security matters. This article examines the diplomatic dispute over territorial waters in relation to its environmental dimensions and social consequences, demonstrating how the challenges of governing transnational space in a water environment greatly complicated everyday life for water users as well as the border work of both states.

Territorial waters — Fisheries — Fishery limits — Exclusive fishery zone — Enforcement of prohibition on fishing in zone by foreign vessels — Use of force — Permissible limits of — Commission of Enquiry.

Disputes — Miscellaneous — Methods of peaceful settlement — Commission of enquiry — Role of — Fact-finding.

Territorial Waters — Breadth of — As affected by claim to offshore islands — Territorial sea of state of Alabama, United States of America.

Territorial Waters — Acquisition of Nationality by Birth in — The Law of Argentina.

Nationality — Acquisition of — By Birth on Foreign Ship in Territorial Waters — The Law of Argentina.

Territorial Waters–Coastal Trade and Fisheries–Prohibition of Fishing Within Three Miles of Coast–Whether “Coast” Includes Islands Near Coast–The Law of France.

Sources of International Law — Customary International Law — Acquiescence as Evidence of International Law.

Bays — Delimitation of — Base-Line — Ten-Miles Rule.

Territorial Waters — Measurement of — Base Line — Sinuosities of the Coast — General Direction of the Coast — The Nature of the Coast and the Determination of the Base Line — Bays — Historic Waters — Ten-Mile Rule — International Character of Delimitation of Territorial Waters — Criteria of Delimitation — Evidence of Existing Practice — Application of the System of Straight Lines — Acquiescence of States Affected by Unilateral Measures of Delimitation — Application of the System of Straight Lines to Specific Areas.

Territorial Waters — Fisheries Inside Territorial Waters — Negligent Infraction of Regulations — Whether Punishable — The Law of Norway.

Territorial Waters — Limits of — Pearl and Chank Fisheries — Landlocked Sea Areas.

Territorial Waters — Fisheries in — Fishing in Violation of Regulations — Effect on Norwegian Courts of Judgment of the International Court of Justice in the Anglo-Norwegian Fisheries Case.

Territorial Waters — Subsoil of — Whether Part of Territory of the State.

Continental Shelf — Whether Part of State Territory — Exclusive Concession Granted with regard to the Entire Territory of the State — Whether Including Continental Shelf — Whether Covering Subsoil of Territorial Waters — Concessionary Contract between Independent Ruler and Private Company.

Territorial Waters — Innocent Passage — Meaning of.

War — Effects of Treaty of Peace — Postliminium — Treaty of Peace with Japan, 1951.

Belligerent Occupation — Nature and Effects of — After Unconditional Surrender — Surrender of Japan at End of Second World War.

Jurisdiction — Exemptions from — Foreign Government-Owned Vessels — Territorial Waters — Innocent Passage — Conditions of — War — Effect of Treaty of Peace — Instrument of Surrender of Japan — Effect on Jurisdiction of Japanese Courts — Effect of Treaty of Peace, 1951 — Postliminium.

International Law — Sources of — General Principles of Law — Interpretation of Concessionary Contract between Independent Ruler and Private Company.

Territorial Waters — In General — Whether Part of State Territory — Subsoil of Territorial Waters.

Treaties — Various Kinds of — Concessionary Agreement between Ruler and Private Company — Interpretation of — Proper Law of the Contract.

Treaties — Interpretation of — Various Rules of — Expressio unius est exclusio alterius — lnterpretation contra projerentem — Contract between Ruler and Private Company.

Treaties — Interpretation of — Preparatory Work — Negotiations Leading to Treaty — Contract between Ruler and Private Company.

Continental Shelf — Nature of — Whether Part of State Territory — Proclamations of Continental Shelf — Whether Declaratory of Existing Law — Exclusive Concession Created with Respect to Entire Territory — Whether Comprising Continental Shelf — Territorial Waters — Subsoil of — Whether Part of State Territory — Concessionary Agreements — Interpretation of — Application of Municipal Rules of Interpretation — General Principles of Law — Agreement between Independent Ruler and Private Company — Negotiations Preceding the Agreement.

Territorial Waters — Status of — Legal Position in the Course of Revolution.

Mandates — Rights and Duties of Mandatory — Article 6 of Mandate for Palestine — Facilitation of Immigration — Inconsistent Municipal Legislation — Competence of Local Courts.

Jurisdiction — Territorial Waters — Legislation — Prevention of Illegal Immigration — Whether Applicable to Aliens — Mandatory Power — Legislative Competence of.

Jurisdiction over the High Seas — Visit, Search and Arrest in Time of Peace — Absence of Ship’s Papers — Absence of Maritime Flag — Enforcernent of Hovering, Revenue and Other Municipal Laws.

Territorial Waters — Criminal Jurisdiction — Power of Mandatory to Legislate for Territorial Waters of Palestine — Immigration — Right of Mandatory to Regulate — Conflict with Terms of Article 6 of Mandate for Palestine — Confiscation of Ship carrying Illegal Immigrants — Immigration Ordinance, 1941.

Territorial Waters — Extent of — Swedish Claims — Fishing Rights — Bays.

Territorial Waters — National Waters — Bays and Roadsteads — The Bay of Brest.

Federal States — Right of State Members of Federal States to Fix the Limit of Territorial Waters.

Boundaries — In General — Right of Member State of Federal State to Fix the Limits of Territorial Waters.

Territorial Waters — Jurisdiction in — Breadth of the Maritime Belt — Nine-Mile Limit.