When Major General Riedesel (of Saratoga fame) was serving in Scotland during the '45 Rebellion, he and other Hessian officers would converse with the Scottish gentry in Latin. However, I think it reached its peak of popularity in Victorian times - especially with the British Army: "peccavi" (Charles Napier - with a nod to Ms Winkworth and Punch), "nunc fortunatus sum" (Colin Campbell) and "vovi" (Lord Dalhousie).