The Order of Civil and Military Merit of Adolph of Nassau (French: Ordre de Mérite civil et militaire d’Adolphe de Nassau) is an order of merit of the Grand Duchy of Luxembourg for meritorious service to the Grand Duke, the Grand-Ducal House and Luxembourg. It was founded in 1858 as a chivalric order of the Duchy of Nassau by Adolphe of Nassau in honor of his namesake and ancestor, Adolf, Count of Nassau, the only member of the House of Nassau to have been Roman King of Germany. After the Duchy of Nassau was annexed by Prussia in 1866 and Adolphe became Grand Duke of Luxembourg in 1890, he revived the order as an order of merit.