Leiden University is the oldest university in the Netherlands. It was founded in February 1575, as a gift from William of Orange to the citizens of Leiden after they had withstood a long siege by the Spanish. It was the first university in the Netherlands to practise freedom of belief and religion, as reflected in the university's motto, Praesidium Libertatis, Bastion of Liberty. It was this atmosphere of freedom of speech that provided the right environment for philosophers such as Spinoza and Descartes to develop their ideas.
The presence within half a century of the date of its foundation of such scholars as Justus Lipsius, Joseph Scaliger, Franciscus Gomarus, Hugo Grotius, Jacobus Arminius, Daniel Heinsius and Gerhard Johann Vossius, at once raised Leiden university to the highest European fame, a position which the learning and reputation of Jacobus Gronovius, Herman Boerhaave, Tiberius Hemsterhuis and David Ruhnken, among others, enabled it to maintain down to the end of the 18th century. At the end of the nineteenth century, Leiden University again became one of Europe's leading universities. At the world’s first university low-temperature laboratory, professor Heike Kamerlingh Onnes achieved temperatures of only one degree above absolute zero of -273 degrees Celsius. In 1908 he was also the first to succeed in liquifying helium and can be credited with the discovery of the superconductivity in metals. Kamerlingh Onnes was awarded the Nobel Prize for Physics in 1913. Three other professors received the Nobel Prize for their research performed at Universiteit Leiden: Hendrik Antoon Lorentz and Pieter Zeeman received the Nobel Prize for their pioneering work in the field of optical and electronic phenomena, and the physiologist Willem Einthoven for his invention of the string galvanometer, which among other things, enabled the development of electrocardiography. These Nobel prize winners, but also the physicists Albert Einstein and Paul Ehrenfest, the Arabist and Islam expert Christiaan Snouck Hurgronje, the law expert Cornelis van Vollenhoven and historian Johan Huizinga, were among those who pushed the university into a place of international prominence during the 1920s and 1930s. In 2005 the manuscript of Einstein on the quantum theory of the monatomic ideal gas (the Einstein-Bose condensation) was discovered in one of Leiden's libraries.
At present, Leiden has a firmly established international position among the top research institutes in many fields, including the natural sciences, medicine, social and behavioural sciences, law, arts and letters. Of the fifty-nine Spinozapremie (the highest scientific award of The Netherlands), fifteen were granted to professors of the Universiteit Leiden. Literary historian Frits van Oostrom was the first professor of Leiden to be granted the Spinoza award for his work on developing the NLCM centre (Dutch literature and culture in the Middle Ages) into a top research centre. Other Spinozapremie winners are linguists Frederik Kortlandt and Pieter Muysken, mathematician Hendrik Lenstra, Carlo Beenakker, who works in the field of mesoscopic physics, Ewine van Dishoeck, astronomer at Leiden Observatory, transplantation biologist Els Goulmy, clinical epidemiologist Frits Rosendaal, Rien van IJzendoorn professor of education and child studies, physicist Jan Zaanen, archeologist Wil Roebroeks, neurologist Michel Ferrari, classicist Ineke Sluiter, social psychologist Naomi Ellemers and astronomer Marijn Franx. Among other leading professors are Wim Blockmans, professor of Medieval History, and Willem Adelaar, professor of Amerindian Languages.