[1] 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.

His father, Johan Ruse, who was the parish priest in Ruinen, belonged to a Huguenot family from eastern France, sympathising with the Protestant theologian Jacobus Arminius.

When Foscolo was appointed to defend Candia in 1651, Ruse decided to leave the army because of problems with his legs, and on his way back, he paid great attention to defence systems and facilities.

[4] He criticized the fortification plans of Amsterdam burgomasters Frans Banninck Cocq, Johan Huydecoper van Maarsseveen, Cornelis Bicker and Nicolaes Tulp.

[12] In Amsterdam Ruse worked as an architect, designed a public building, a few houses and invested in the import of Norwegian timber piles and real estate, which was intended for shipwharves.

Ruse justified his efforts explaining that Denmark needed to be protected from the south, with additional defences in Sonderburg and Friedrichsort on the western shore of Kiel Fjord.

[16] He had hoped to undertake a much more extensive project on both sides of the River Eider but this was hampered by resistance from Hans von Schack, an influential military expert.

At the beginning of Christian V's reign, he rebuilt the entrenchments on a small island in the River Elbe and completed a comprehensive report on the fortification system for the Danish-Norwegian monarchy.

Despite considerable success in Norway, Ruse was not happy about his stay there as it caused him appreciable losses on his interests in Rendsburg while his professional expertise was no longer in demand.

However, in the absence of manpower and supplies and in the face of opposition from Field Marshal Joachim Rüdiger von der Goltz who was given the supreme command of Scania, he was unable to complete the assignment.

Ruse's defence consisted of a lengthy complaint criticising lack of support from von der Goltz, a position which was upheld by the examining committee.

[14] On 4 December 1677, Ruse obtained his retirement and pending remuneration, with instructions not to serve Denmark-Norway's enemies and to return to Denmark without delay if the king so required.