National parochialism is the tendency to cooperate more with ingroup than outgroup members. Angelo Romano, Matthias Sutter, James Liu, Toshio Yamagishi & Daniel Balliet studied national parochialism across different nations and conclude in their publication in Nature Communications that it is a ubiquitous…

This PhD project investigates the forms, functions, meanings, and socio-cultural values embedded in Palenda, in order to understand how it reflects and shapes the worldview of the Muna people (Mieno Wuna) through metaphor.

Is our musicality unique? To find out, the Bird Singalong Project brings together singing parrots from all over the world. Do you have a parrot that sings or whistles along to songs and would you like to help us? Sing up now!

The World Politics Major at Leiden University College The Hague examines the big ideas and the powerful forces – political, military, economic, social and cultural – that shape the world at every level, from the global to the local and everything in between. Political conflict is a key driver of many…

Material Crossovers

Lecture

Recently, Austrian physicists succeeded in placing minuscule metal spheres with a diameter of 0.000008 millimetres into superposition.

Indigenous Latin American artifacts have attracted the interest of Europeans since the earliest moment of contact between Europeans and the Indigenous peoples of the Americas. The ERC-funded BECACO project uses an innovative multidisciplinary framework to investigate the provenance of ethnographic and…

1000 Years of World History in 100 Old Maps.

Optimally solving real-world expensive Black-Box Optimization (BBO) problems w.r.t. real-world constraints, such as wall-clock time and computational costs, is extremely difficult and tedious.

In Humanity’s End As A New Beginning, Emeritus Professor Mineke Schipper reflects on myths about ‘the end’.

In this opinion article published in World Development, the authors present five research and policy priorities. While it is clear that ‘pluriversal’ designs need to guide the way forward (Kothari et al 2019), defining a set of key pillars can provide direction and purpose across this pluriversality.…

There are several committees within the IBL that are crucial for organizing and coordinating research, education and finances. Among the lesser-known of these committees is the IBL Institute Council (IC or Instituutsraad, IR). The purpose of the IC is to serve as a link between IBL members and management…

Webinar with Q&A

This book examines the history of The Netherlands in a way that connects global processes to local developments.

This COIn Grant 2025 awarded project allows Leiden University researchers and students to do research on the world’s largest corpus of digitized Ottoman language periodicals and books.

Classical mathematical models treat space and time as a continuum, while it is sometimes more useful to regard it as granular. Hupkes is studying what this means for a number of important patterns that are often found in computer calculations and in nature.

Insect egg development in a warming world: the eco-evo-devo of embryonic developmental time: What is the genetic basis of developmental time?

The World of the Fullo takes a detailed look at the fullers, craftsmen who dealt with high-quality garments, of Roman Italy. Analyzing the social and economic worlds in which the fullers lived and worked, it tells the story of their economic circumstances, the way they organized their workshops, the…

On Tuesday 10 September 2024 May Shaddel Basir successfully defended a doctoral thesis and graduated.

A portrait of the complex historical process of over 500 years of European colonialism in the New World.

This book examines the critical role of information and knowledge in early modern Europe's global pursuits, exploring challenges in trusting distant information, the development of doubt in intercultural encounters, and the impact of misinformation.

Are there general principles or values that should govern our actions as moral agents and/or as political subjects?

NTER-SECTION is a peer-reviewed, open-access journal focusing on contributions from junior archaeological researchers at Leiden University. The journal offers an accessible platform for the publication of individual research by undergraduate and graduate students. The Editorial Board consists of PhD…

Imagining the Americas in Print contains eleven essays, seven of which have been published before and four of which are new.

This book published by Oxford University Press discusses religion and trade in world history.

Bacteria caught red-handed, deeply frozen just as they were about to cause Lyme’s disease. Ariane Briegel is wildly enthusiastic about the wonders she observes thanks to three elements: a freezing technique, a camera-equipped microscope, and AI. ‘It’s fascinating. Every single cell is different.’

During the period 500–1000 CE Egypt was successively part of the Byzantine, Persian and Islamic empires. All kinds of events, developments and processes occurred that would greatly affect its history and that of the eastern Mediterranean in general. This is the first volume to map Egypt's position in…

The historiography of the Bretton Woods conference of July 1944 is dominated by the personal clash between the principal negotiators, Harry Dexter White of the United States and John Maynard Keynes of Britain.

Sheltering is an immediate human need and determines well-being andhealth.

Who had a say in making decisions about the natural world, when, how and to what end? How were rights to natural resources established? How did communities handle environmental crises? And how did dealing with the environment have an impact on the power relations in communities?

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…

Japan's Occupation of Java in the Second World War draws upon written and oral Japanese, Indonesian, Dutch and English-language sources to narrate the Japanese occupation of Java as a transnational intersection between two complex Asian societies, placing this narrative in a larger wartime context of…

On the occasion of the 80th anniversary of the magna carta of civil aviation, the Convention on International Civil Aviation (Chicago Convention 1944), Professor Steven Truxal has written a leading piece for the European Civil Aviation Conference: The Chicago system: a steadfast legal blueprint for…

Carl Li defended his thesis on 30 June 2015

A neolithic settlement on the Dutch North Sea coast c. 3500 CAL BC.

Security and Legitimacy is one of the three organisational clusters of the Institute of Political Science.

Dr. Gruni published an article on the impact on sustainable development in the EU Common Commercial Policy of recent Opinion 2/15 CJEU on the Global Trade and Customs Journal.

Machine Learning is becoming a more and more substantial technology for industry.

This project investigates how early print media covered distant but urgent geopolitical conflicts, using newspapers from the Low Countries, north and south.

On Friday 16 May Juul Eijk successfully defended a doctoral thesis and graduated.

In early medieval England, there was an interest in the history of the Roman Empire and kings adopted such imperial titles as 'imperator' or 'basileus'. How can we explain this interest and what functions did imperial ideas and the reception of the classical world serve in early medieval England?

Today’s socio-economic challenges aren’t new. In the centuries after the retreat of the Roman state people with different backgrounds and with different ways of life somehow managed to build and maintain a complex economic system in northern Gaul that would produce the ruling dynasties of Europe. By…