This conference explores the early modern law of the sea as a contested legal regime forged through warfare, commercial rivalry, jurisdictional overlap, and asymmetries of power. It invites contributions examining how conflict, enforcement practices, neutral navigation, and maritime litigation contributed to the historical formation of the law of the sea between the fifteenth and eighteenth centuries.

Argument

Concept and Rationale : The early modern law of the sea did not emerge as a coherent or pacified body of rules. Rather, it took shape as a fragmented and deeply contested legal regime. It was forged through recurrent warfare, commercial rivalry, and persistent struggles over jurisdiction and enforcement at sea. The pelagic arena was characterised by overlapping jurisdictions, uneven enforcement, and profound asymmetries of power (Benton, 2010). The freedom of the seas (‘Mare Liberum’) did not operate as a stable peacetime principle. It was repeatedly restricted, negotiated, and redefined in moments of conflict, particularly through disputes concerning maritime jurisdiction, economic warfare, neutral navigation, and prize-taking.

Hence, several methodological questions arise. Can we chart the deeper structures and long-term evolutions of the law of the sea and, at the same time, remain historically grounded and relevant to contemporary debates ?

Recent scholarship has challenged the idea that the law of the sea gradually restrained violence at sea. Instead, norms were forged, tested, and transformed through concrete conflicts over sovereignty, jurisdiction, and neutral navigation (e.g. Steinberg, 2001 ; Benton, 2010 ; Schnakenbourg, 2015 ; Calafat, 2019 ; Cattelan, 2025). This perspective invites a rethinking of the law of the sea not as a dependent variable of early modern conflict, but as one of its crucial products. The present conference builds on this emerging insight and seeks to explore its broader implications across different regions, actors, and legal contexts.

This conference invites contributions that approach the law of the sea as a historically produced normative regime, examined as (1) a body of legal argument, a set of institutional (2) practices, and a (3) field of political struggle. It seeks to foster dialogue across legal history, international law and the histories of ideas, diplomacy, warfare, and empire, bringing together scholars attentive to different sources, actors and objects (doctrine, archives, institutions, legal reasoning, institutional practice, and material interests). The conference situates the law of the sea within broader processes of state formation, imperial competition, and global connectivity, including its interaction with commercial and maritime legal practices (Félicité, 2024).

This conference takes a broad analytical perspective, to seal a series of three encounters organised under the aegis of FWO Junior Fundamental Research Project G016122N. While earlier meetings in this series focused primarily on neutrality as a legal status, diplomatic strategy, and social practice —particularly from the perspective of small and medium powers— the present symposium shifts the analytical focus : recurrent conflicts over neutrality, belligerent rights, maritime jurisdiction, and enforcement mechanisms did not merely test existing norms. These instances were crucial to the historical formation of the law of the sea as a contested legal regime. In this sense, neutrality is approached as a formative force in the making of the law of the sea across judicial, diplomatic, and commercial arenas.

The conference aims to offer a synthetic reinterpretation of the relationship between mare liberum and mare clausum, peace and war, neutrality and coercion, situating the early modern law of the sea within the longer history of international law without assuming linear trajectories or teleological outcomes. It also invites reflection on the enduring legacies of early modern maritime practices for later codification efforts and contemporary debates on ocean governance in an increasingly polycentric world (Mawani, 2023 ; Ranganathan, 2016, 2020).

Finally, the conference welcomes contributions addressing different maritime regions and circuits, including —but not limited to— the Mediterranean, Atlantic, and Indian Ocean worlds, as well as interactions between different legal orders and actors (Anand, 1983 ; Khalilieh, 2019 ; Subrahmanyam, 2024 ; Po, 2018). We particularly welcome contributions on cross-cultural legal encounters and concrete sites of norm production, such as courts, diplomatic practices, commercial litigation, port regulations, and contractual arrangements.

Key Questions

• The conference invites contributions addressing one or more of the following questions :
• What kind of legal regime was the early modern law of the sea ?
• How can it be understood as a historically contingent and contested normative order rather than a coherent or stabilised body of rules ?
• How did warfare shape the law of the sea ?
• In what ways did recurring conflicts over maritime jurisdiction, belligerent rights, neutrality, blockade, contraband, and prize-taking contribute to the production and transformation of legal norms at sea ?
• How was the law of the sea articulated, applied, and contested in daily practice ? What roles did courts, diplomatic channels, port authorities, consular institutions, and commercial actors play in the everyday functioning of this legal regime ?
• How did neutrality operate as a formative force within the law of the sea ? How were legal boundaries between peace and war at sea shaped by disputes and agreements involving neutral navigation ?
• How did individuals and non-state actors exercise legal agency at sea ? The mobilisation of multiple normative orders —public, commercial, and customary by merchants, shipmasters, insurers, chartered companies, or private entrepreneurs — to pursue commercial, political, or strategic objectives is central here.
• How did different connected spaces and regions shape a distinct legal practice ? How did practices take shape across and between different maritime regions and circuits, including interactions between European and extra-European legal orders ?
• What are the longer-term implications of early modern practices of the law of the sea ? How did early modern solutions and conflicts inform later codification efforts and continue to resonate in contemporary debates on ocean governance ?

Thematic Areas (Indicative)

The following thematic areas, which constitute the thematic translation of the questions highlighted above, articulate different dimensions of the early modern law of the sea as a contested legal regime produced through conflict, commerce, and legal practice. They are intended to be read as analytically connected rather than as parallel or autonomous agendas. They are indicative rather than exhaustive.

The sea as a legal and spatial order

Maritime jurisdiction ; territorial waters ; ports, straits, and littoral zones ; sovereignty and access ; legal pluralism at sea ; competing claims to control, passage, and enforcement.

War, commerce, and neutrality in the law of the sea

Naval warfare and economic conflict ; blockade, contraband, and continuous voyage ; prizetaking and adjudication ; neutrality as legal status, diplomatic strategy, and practical resource ; coercion, enforcement, and asymmetries between belligerents and neutrals.

Institutions and practices producing the law of the sea

Courts (including admiralty and prize courts) ; diplomatic correspondence ; consular jurisdictions ; port authorities and regulatory regimes ; chartered companies ; litigation, arbitration, and everyday legal practice. Contributions grounded in specific sources or sites of norm production are particularly welcome.

Agency and normative pluralism within the law of the sea

The role of individuals and non-state actors —such as merchants, shipmasters, insurers, private entrepreneurs, and colonial intermediaries— in mobilising a plurality of normative orders, including the law of nations, domestic legislation, commercial and maritime law, urban statutes, customary norms, and private contracts.

The law of the sea across regions, empires, and legal encounters

Comparative and transregional perspectives ; interactions between European and extraEuropean legal orders ; cross-cultural legal encounters ; circulation, translation, and contestation of norms governing maritime space in different oceanic worlds. 6. From early modern practice to modern/contemporary ocean governance

Long-term continuities and ruptures in the law of the sea ; armed neutrality and collective enforcement ; early modern legacies in later codification efforts and contemporary debates on ocean governance.

Disciplinary Scope : The conference welcomes contributions from legal history, the history of international law, maritime and naval history, diplomatic and political history, economic history, and international law scholarship with a historical or theoretical orientation. Interdisciplinary, critical, and transregional approaches are particularly encouraged. Early-career researchers are warmly invited to submit proposals.

Format : The conference is conceived as a focused, discussion-oriented event. Draft papers will be circulated in advance to facilitate in-depth exchange. Presentations will be kept at 20 minutes for each speaker in order to prioritise collective discussion and comparative discussion.

Submission Guidelines 

Please submit an abstract of no more than 350 words and a short biographical note of up to 150 words to : stefano.cattelan@vub.be.

• Submission deadline : 15 May 2026
• Notification of acceptance : 1 June 2026
• Draft papers (for pre-circulation among participants) : 20 October 2026
• Conference : 19-20 November 2026, Ostend, Belgium

Publication : Following the conference, selected contributions will be submitted to a special issue in an international peer-reviewed journal (preferably open access).

Practical Information : The organisers aim to secure funding to cover organisational costs and, where possible, to offer limited support for travel and accommodation, particularly for earlycareer researchers and scholars without access to dedicated research funds. Further practical information will be communicated to accepted participants.

Scientific comittee

• Prof. dr. Frederik Dhondt, Vrije Universiteit Brussel, Belgium
• Dr. Stefano Cattelan, Vrije Universiteit Brussel, Belgium

Indicative references 

Alimento, Antonella (ed.), War, Trade and Neutrality : Europe and the Mediterranean in the Seventeenth and Eighteen Centuries (Milano, 2011).

Id., and Stapelbroek, Koen (eds.), The Politics of Commercial Treaties in the Eighteenth Century (Cham, 2017).

Anand, Ram P., Origin and Development of the Law of the Sea. History of International Law Revisited (The Hague/Boston/London, 1983).

Benton, Lauren and Perl-Rosenthal, Nathan (eds.), A World at Sea : Maritime Practices and Global History (Philadelphia, 2020).

Benton, Lauren, A Search for Sovereignty. Law and Geography in European Empires, 1400-1900 (Cambridge, 2010).

Calafat, Guillaume, Une mer jalousée : contribution à l’histoire de la souveraineté (Méditerranée, XVIIe siècle) (Paris, 2019).

Cattelan, Stefano and Frederik Dhondt (eds.), Small Power Neutrality and the Law of the Sea in the Long Eighteenth Century (1650–1800). Law as Argument in the Pelagic Arena (Leiden/Boston, 2025).

Cattelan, Stefano and Louis Sicking. ‘The Coastal Seas in International Law : Contextualising Grotius’s De iure belli ac pacis’, Grotiana, 46(1) (2025), 43-65.

Cattelan, Stefano, Mare Clausum : The Formation of the Law of the Sea in Pre-modern State Practice and Legal Doctrine (c. 1350–1650) (Leiden/Boston, 2025).

Dhondt, Frederik, ‘“Arrestez et pillez contre toute sorte de droit” : Trade and the War of the Quadruple Alliance (1718-1720)’, Legatio : The Journal for Renaissance and Early Modern Diplomatic Studies, 1 (2017), 98-130.

Id., ‘Delenda est haec Carthago. The Ostend Company as a Problem of European Great Power Politics (1722-1727)’, Belgisch Tijdschrift voor Filologie en Geschiedenis/Revue Belge de Philologie et d’Histoire, 93 (2015), 397-437.

Félicité, Indravati, Le Saint-Empire face au monde. Contestations et redéfinitions de l’impérialité (XVe-XIXe siècle) (Paris, 2024).

Ford, John D., The Emergence of Privateering (Leiden/Boston, 2023).

Harding, Richard, Seapower and Naval Warfare, 1650–1830 (London, 2002).

Khalilieh, Hassan S., Islamic Law of the Sea : Freedom of Navigation and Passage Rights in Islamic Thought (Cambridge, 2019).

Mancke, Elizabeth, ‘Early Modern Expansion and the Politicization of Oceanic Space’, Geographical Review, 89(2), 225-36.

Mawani, Renisa, ‘The law of the sea’, in Peter D. Burdon and James Martel (eds.), The Routledge Handbook of Law and the Anthropocene (London, 2023), 115-29.

Müller, Leos, Neutrality in World History (New York, 2019).

Neff, Stephen C., The Rights and Duties of Neutrals : A General History (Manchester, 2000). Po, Ronald C, The Blue Frontier : Maritime Vision and Power in the Qing Empire (Cambridge, 2018).

Ranganathan, Surabhi, ‘Decolonization and International Law : Putting the Ocean on the Map’, Journal of the History of International Law, 23(1) (2020), 161-83.

Id., ‘Global Commons’, European Journal of International Law, 27(3) (2016), 693-717.

Schnakenbourg, Éric, Entre la guerre et la paix : Neutralité et relations internationales, XVIIe– XVIIIe Siècles (Rennes, 2013).

Sicking, Louis, ‘The Pirate and the Admiral : Europeanisation and Globalisation of Maritime Conflict Management’, Journal of the History of International Law, 20(4) (2018), 429-70. Stapelbroek, Koen (ed.), Trade and War : The Neutrality of Commerce in the Inter-State System (Helsinki, 2011).

Steinberg, Philip E., The Social Construction of the Ocean (Cambridge, 2001).

Strootman, Rolf, van den Eijnde, Floris, and van Wijk, Roy (eds.), Empires of the Sea. Maritime Power Networks in World History (Leiden, 2019).

Subrahmanyam, Sanjay, Across the Green Sea : Histories from the Western Indian Ocean, 1440– 1640 (Austin, 2024).

Wani, Kentaro, Neutrality in International Law. From the Sixteenth Century to 1945 (London/New York, 2017).