Henrik Ruse, Baron of Rysensteen (né Henrik Ruse 9 April 1624 – 22 February 1679) was a Dutch officer and fortification engineer. Following a period when he served in various armies in Germany and Italy, he wrote a well-researched book documenting the latest trends in fortification systems across Europe. As a result, he was entrusted with commissions for improving defences in his native Amsterdam, in Germany, and finally in Denmark and Norway where, benefitting from the support of the monarchy, he first became a general and later a baron. Ruse died in Sauwerd near Groningen in the Netherlands. Source: Wikipedia (en)