The International League Against Epilepsy was founded in Budapest in 1909. Its history mirrors the development of modern epileptology: classification, international research, specialist education, advocacy and the creation of a shared clinical language.
Budapest, 1909
The ILAE was formed on 30 August 1909 during an International Congress of Medicine in Budapest. Early organisers included József Donáth and Louis Muskens.
The new organisation adopted the journal Epilepsia as its scientific journal and began building national committees.
An international idea before international medicine was easy
At the beginning of the twentieth century, epilepsy research was fragmented across countries and specialties. International communication was slow, terminology varied and stigma was deeply embedded in law and society.
The League’s founders saw epilepsy as requiring scientific, clinical, social and legal cooperation across borders.
Interrupted by world wars
World War I disrupted the young organisation and publication of Epilepsia. The League had to be re-established after the war.
World War II again interrupted international activity, but national chapters resumed collaboration afterwards.
Classification becomes one of the League’s defining roles
Over decades the ILAE developed international systems for classifying seizures, epilepsies and epilepsy syndromes.
These systems changed as EEG, neuroimaging, genetics and clinical neuroscience changed what was known about epilepsy.
Epilepsia and international research
Epilepsia became the League’s flagship journal and a major publication forum for epilepsy science.
Commissions, task forces and working groups allowed experts from different regions to collaborate on definitions, treatment issues, epidemiology, surgery, paediatrics, genetics and other areas.
From specialist society to global network
The ILAE now includes more than 120 national chapters. Its work extends from highly specialised epilepsy centres to guidance intended for lower-resource settings.
Translation and international usability have become explicit goals of modern classification projects.
Why the organisation matters to patients
The effect of the ILAE is often indirect. A patient may never hear the organisation’s name, but the terminology in a clinic letter, the definition of drug-resistant epilepsy, a seizure-classification term or an epilepsy-syndrome diagnosis may originate from ILAE work.
The League’s history is therefore also a history of how epilepsy became an internationally standardised medical discipline.
Related reading
Sources and further reading
- ILAE History: Introduction
- ILAE History: The Onset — Budapest 1909
- ILAE History and Archives
- ILAE Centenary History
Evidence checked: September 2026.