Petrus Forestus

In 1540 he began a so-called peregrinatio Academica, an educational journey in which he visited several European universities in order to acquire detailed knowledge of medicine.

Forestus was invited by the Curators of the newly founded Leiden University to attend the opening ceremony on 8 February 1575.

He participated in the festive procession as "doctor and professor of medicine" and stayed in Leiden until 12 February in order to sign the Statutes of the new university.

After the assassination of Prince William of Orange on 10 July 1584, Forestus conducted the autopsy and embalming together with his colleague from Delft, Cornelius Busennius.

Part of an unpublished manuscript was titled: Vander Empiriken, Landloeperen ende Valscher Medicynsbedroch (On charlatans, frauds, and the trickery and deceit with false medicine).

The Observationes were personal perceptions of patients and diseases, and formed the basis for the subsequent Scholia, initially dedicated as a separate monograph to personal acquaintances such as Prince Maurice of Orange, and city governments, like those of Alkmaar, Delft, Leiden, Amsterdam and Enkhuizen.