In 1575, the emerging Dutch Republic did not have any universities in its northern heartland. The only other university in the Netherlands was in southern Leuven, firmly under Spanish control. The scientific renaissance had begun to highlight the importance of academic study, so Prince William founded the first Dutch university in Leiden as a reward for the heroic defence of Leiden against Spanish attacks in the previous year. Ironically, the name of Philip II of Spain, William’s adversary, appears on the official foundation certificate, as he was still the de jure count of Holland. It is traditionally said that the citizens of Leiden were offered the choice between a university and a certain exemption from taxes, and that the citizens believed that a tax law could be rescinded, whereas the great universities of Europe had survived for many centuries. Originally located in the convent of St Barbara, the university moved to the convent of the White Nuns in 1581, a site which it still occupies, though the original building was destroyed in 1616.
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.
The Hortus Botanicus of Leiden is the oldest botanical garden of the Netherlands, and one of the oldest in the world. It is located in the southwestern part of the historical centre of the city, between the Academy building and the Leiden Observatory.
In 1587 the young University of Leiden requested the burgomasters of Leiden permission to establish a hortus academicus behind the Academy building, for the benefit of the medicine students. Permission was granted in 1590, and as prefect was appointed the famous botanist Carolus Clusius (1526–1609), who arrived in Leiden in 1593. Clusius’ knowledge, reputation and international contacts allowed him to set up a very extensive plant collection. Clusius also urged the Dutch East India Company (VOC) to collect plants and (dried) plant specimens. The original garden set up by Clusius was small (about 35 by 40 meters), but contained more than 1000 different plants.
The collecting of tropical (from the Indies) and sub-tropical (from the Cape Colony) plants was continued under Clusius’ successors. Especially Herman Boerhaave (1668-1738, prefect from 1709-1730), contributed greatly to the fame of the Hortus with his efforts to collect new plants and specimens, and with his publications, such as a catalog of the plants then to be found in the Hortus.
Another major contribution to the collections was made by Philipp Franz von Siebold, a German physician who was employed on Deshima (Japan) by the VOC from 1823 until his expulsion by Japan in 1829. During that period he collected many dried and living plants from all over Japan (as well as animals, ethnographical objects, maps, etc.), and sent them to Leiden.
The first greenhouses appeared in the Hortus in the second half of the 17th century, the monumental Orangery was built between 1740 and 1744. From its original plan the Hortus was progressively expanded until 1817. In 1857, a part was used for building the new Leiden Observatory.