Menno, Baron van Coehoorn (1641 - March 17th 1704), is a soldier and military Engineer Dutch of Swedish origin. He is in the beginning many innovations in the Armes of seat and the techniques of Fortification.

Biography

He is born with Leeuwarden in Frise, receives an excellent education general practitioner and soldier. He becomes with old 16 years Capitaine in the Dutch army and takes share with the defense of Maastricht during the Guerre of Holland (1673) like to the seat of Grave (1674), where small the mortars (called coehorns) invented by itself was the cause of important losses French side. He is promoted with the rank of Colonel for his exemplary control during the battle of Seneffe (August 11th 1674) and is also present at the battles of Cassel (1677) and of Saint-Denis (1678).

The geopolitical situation pushes it to pay its attention on the art of the fortification, the warlike events make it realize that the methods applied are from now on obsolete. With its first publication, Versterchinge de Vijfhoeks puts ale syne Buytenwerken (Leeuwarden, 1682), it attracts continuation the attention of its contemporaries and enters a controversy impassioned with a rival engineer, Louis Paen (Leeuwarden, 1682, 1683; the copies are with the Dutch equivalent of the Ministry for Defense). This work is especially followed with many interests by the military authorities, and Coehoorn is seen entrusting the rebuilding of many fortresses in the United Provinces. This activity takes to him a good portion of its time during all its career, and its experiment places it as being the principal rival of Vauban. He formulates his ideas some time later in his masterpiece entitled Nieuwe Vestingbouw (Leeuwarden, 1685), in which he fixes three systems whose characteristic is the multiplicity of the works as well as the great angularity of those, which prove eminently suitable for the landscapes of plains and marshes which compose the landscapes of the Netherlands.

He borrows several details from work of his Dutch predecessor Freytag, in the same way at Albrecht Dürer, like to the German engineer Daniel Specklin, he in general aimed more to the adaptation of its principles to the particular needs for each site than to the construction of a geometrically and theoretically perfect Forteresse. Throughout its career, it forever hesitated to separate its own rules to face the exceptional cases, as it was the case for Groningue. The following editions of Nieuwe Vestingbouw were born in Dutch (1702, and frequently afterwards), in English (London, 1705), in French (Wesel, 1705) and in German (Düsseldorf, 1709).

During the Guerre of the league of Augsburg (1688 - 1697) Coehoorn is useful as a Brigadier. He is particularly distinguished with the battle from Fleurus in 1690, like in 1692 during the head office of Namur, a fortress of his own creation. Namur was taken by Vauban, but Coehoorn had its revenge later three years when same place-strong on which meanwhile Vauban had brought its improvements fell under its attack. Coehoorn became Lieutenant-general and Inspector-general of the fortresses of Holland, and the people high-Germans as well as its own compatriots honoured it. It then ordered a body of the army of the duke of Marlborough of 1701 with 1703, its competences and its value was of a great help in this war of permanent headquarter in the Netherlands. The fast rendering of the fortress of Bonn and the seat of Huy of 1703 were the crowning of its success. At the beginning of the following countryside, it was about to confer with Marlborough when it died of Apoplexie to Wijckel on March 17th, 1704.

Posterity

Its first system at summer applied to many places in Holland in particular Nimègue, Breda and Bergen COp Zoom. Mannheim in Germany was also strengthened in this manner, however that the second system was him applied to Belgrade and Timişoara.

He wrote on art to strengthen the places a work become traditional, translated under the title of Nouvelle Fortification , $the Hague, 1706. He left his name to the mortars in Cohorn, that only one man can operate.

His/her son, Gosewijn Theodor van Coehoorn, wrote his biography (republication Syperstein, Leeuwarden, 1860)