How do first-hand narratives of war of commanders in the front line relate to the official narrative of the Eighty Years’ War?

The debate about state behaviour in cyberspace may be set in the wrong legal key.

This edited volume by Jeff Fynn-Paul pushes forward the debate on the role of entrepreneurs in making war and building states in Europe and the Ottoman Empire.

An investigation into how racial stereotypes were created and used in the European Middle Ages.

Knowledge that helps protect the Netherlands and Europe from military and cyber threats.

Yi Kyubo (1168–1241) was the foremost writer and poet of the Koryŏ dynasty (918–1392). Not Everything Unfolds as Anticipated is a miscellany of work from his Tongguk Yi Sangguk chip, a collection containing more than two thousand texts and considered the earliest substantial oeuvre of a Koryŏ writer…

By training with virtual opponents known as computer generated forces (CGFs), trainee fighter pilots can build the experience necessary for air combat operations, at a fraction of the cost of training with real aircraft.

Our subscribers have written several publications about international security issues.

Terwijl NAVO-landen hun defensiebudgetten fors verhogen, ontstaat ruimte voor start-ups om innovatieve technologie te leveren. De flexibiliteit en snelheid maken hen aantrekkelijk voor defensie, maar de opmars brengt ook risico’s met zich mee, waarschuwt Louisa Handel-Mazzetti, promovenda bij Lucht…

In the fall of 2021, Cleveringa professor Roméo Dallaire and world experts shared their thoughts about PTSD, children’s rights, war crimes, humanitarian law, and peacekeeping in a series of conversations about leadership and moral dilemma during times of conflict and crisis.

Using object assemblages to reconstruct activities, modes of deposition and abandonment at the Late Bronze Age dunnu of Tell Sabi Abyad, Syria.

The Netherlands Ministry of Defense and Ministry of Security and Justice have requested the Centre for Terrorism and Counterterrorism to complete a research project on cyber governance from a policy perspective. The results of this project will contribute to the deliverables of the fourth International…

In a podcast episode of 'New Books in History' Claire Weeda talks about her book 'Ethnicity in Medieval Europe 950-1250: Medicine, Power and Religion'.

Dario Fazzi

Proceedings of the Eighteenth Annual Theoretical Roman Archaeology Conference Amsterdam 2008

This project aims to excavate and date the setting of the east gate of the Roman fortress of Udhruḥ. This will be compared with other Diocletianic military installations from the region. We also hope to retrieve another gate inscription which can shed light on the function and political embedding of…

Ten years later, a group of veterans still struggle daily with the effects of their deployment to Afghanistan. Sanne van der Wal, a PhD candidate at the Leiden University Medical Center (LUMC), conducted research into the effects of PTSD.

Meet the core staff behind Global Transformations and Governance Challenges, which consists of a Professor, a postdoctoral researcher, three PhD candidates, and a Programme Officer.

Fabio Cristiano contributed two chapters to the Routledge Companion to Global Cyber-Security Strategy, edited by Scott N. Romaniuk and Mary Manjikian.

The Hague Program for Cyber Norms, a research program at the Institute of Security and Global Affairs, published its first policy brief, in which Dennis Broeders, Sergei Boeke and Ilina Georgieva explore the role of intelligence agencies in cyberspace and the (im)possibilities of oversight and regulation…

French title: Communication et violences dans le Guéra et le Moyen-Chari (Tchad) de 1940 à 2010. This research investigates the relationship between the introduction of new means of communication and violence experienced by the local populations in the Moyen-Chari and the Guéra regions in Chad from…

This PhD project investigates the argumentative-rhetorical strategies by which the Russian state attempts to substantiate the legitimacy of its war against Ukraine.

Nick Cohen interviews Andrew Gawthorpe about the current geopolitical situation, particularly focusing on America's disastrous war with Iran and its broader implications.

It is widely known that conflict parties engage in ceasefires for a variety of reasons, but how do these reasons relate to the military and political aspirations of conflict party leaders?

Eine Analyse materieller Kultur römischer Kolonien in der Mikroregion von Suessa Aurunca, Minturnae und Sinuessa

The Dutch and English East India Companies were formidable organizations that were gifted with expansive powers that allowed them to conduct diplomacy, wage war and seize territorial possessions. But they did not move into an empty arena in which they were free to deploy these powers without resista…

Malte Riemann examines the evolution of the mercenary concept. He suggests that notion of mercenary emerged in 19th-century Europe.

In this article Vanessa Newby discusses how the ANZUS states of United States, Australia, and New Zealand that sit on the fringes of the Asia-Pacific, are increasingly using their armed forces to deliver Humanitarian Aid and Disaster Response (HADR) as a way of engaging with the region.

The transformation of the myriad of medieval kingdoms, principalities, local lordships, city-‘states’ and peasant ‘republics’ into ‘modern’ states, claiming some measure of sovereignty, remains one of the core themes of European history, because it gets down to the very root of the (idea on the) Europe…

Volume I of The Cambridge History of Strategy offers a history of the practice of strategy from the beginning of recorded history, to the late eighteenth century, from all parts of the world.

Roman Nijmegen is not only the largest archaeological micro-region in the Netherlands, but also one of the most extensively excavated settlement complexes of the Roman period north of the Alps.

Where are the Women in Global Governance and in peace processes?

Numismatic research of Roman coin hoards in the Netherlands. The use of numismatic sources is incorporated in Claes’s research project “Dialogues of Power”. This project aims to analyse the legitimising dialogue between Roman emperors and their Germanic legions during the so-called “crisis of the third…

Since May 2026, Roy de Ruiter has been strengthening the Institute of Political Science as professor of Maritime Strategy by special appointment. This chair is a collaboration between the Dutch Royal Association of Naval Officers (KVMO) and Leiden University. A conversation about change versus continuity…

The acquisition and administration of the possessions of the “Teutonic House” in Utrecht, and its dependencies, in the Middle Ages until c.1600.

Should the law and norms applicable to armed conflict include a distinct category covering the transition from armed conflict to peace, jus post bellum, and if so what are its characteristics?

In this publication the results of the analyses of the Roman harbour of Voorburg-Arentsburg (NL) are presented. This fully inclusive and integrated study of more than 1000 pages is published in two volumes. The publication is written in Dutch, but has got an extensive synthesis/summary in English.

This article illustrates how the term 'dual use' has become associated with a broader dichotomy between ‘legitimate’ and ‘illegitimate’ purposes.

Escalating tensions in South China Sea have epitomized US–China relations for nearly a decade. Warning signs of a possible collision between a rising China and steadfast US, bring to light the need to think about ways that can halt and reverse the intensification of their confrontational moves.

Prince, Pen, and Sword offers a synoptic interpretation of rulers and elites in Eurasia from the fourteenth to the eighteenth century. Four core chapters zoom in on the tensions and connections at court, on the nexus between rulers and religious authority, on the status, function, and self-perceptions…

Terrorism destabilizes governments, undermines civil society, threatens social and economic development, endangers democracy, and directly impacts human rights. The extraordinary events on 9/11 turned counterterrorism into a global governance project. The global collaboration is unprecedented with traditional…

On 22 June, Najib Amin defended the thesis 'State-building, lawmaking, and criminal justice in Afghanistan: a case study of the prison system’s legal mandate, and the rehabilitation programmes in Pul-e-charkhi prison'. The doctoral research was supervised by Jan Michiel Otto and Pauline Schuyt.

Embracing the Provinces is a collection of essays focused on people and their daily lives living in the Roman provinces, c. 27 BC-AD 476. It offers an overview of current research on Roman provinces and frontiers, deconstructing some long-held preconceptions and providing refreshing insights into unexplored…

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