sentences:  The regiment garrisoned Gravelines and Dunkirk during the 1756 to 1763 Seven Years' War and in July 1770, Louis XV gave him the Order of Military Merit.Elcho divided his time between France and Switzerland, where he bought a property in Neuchatel and became a Swiss citizen.On 9 September 1776, he married Sofia von Üxküll-Gyllenband (1756–1777), at Beutal in Switzerland, daughter of Reichsgraf Friedrich von Üxküll-Gyllenband, a minister of the Duchy of Wurttemberg.