Adrian was born in 1603, to Wilhelm von Enkevort a member of the noble family, originating in the Duchy of Brabant. Adrian followed his father's footsteps entering the service of the Electoral Bavarian army. He later joined the forces of Bavaria's ally the Holy Roman Empire, serving under Imperial generalissimo Albrecht von Wallenstein. During the course of the Thirty Years' War, Enkevort distinguished himself at the Battle of Lützen (1632). He represented the empire in the course of its negotiations with Bernard of Saxe-Weimar, later joining one of Adam Erdmann Trčka von Lípa's infantry regiments in the rank of Oberstleutnant. He appears to have not been affected by an internal purge which resulted in the assassination of Wallenstein and Trčka and the subsequent persecution of their close associates. In July 1635, he was promoted to the rank of colonel and dispatched to Breisach where he joined Charles of Lorraine's campaign to reconquer his duchy from the French and the Bernhardines. In October, after an initial success the Imperial-Bavarian army operating in the region was decimated by an outbreak of Hungarian spotted fever. In 1636, Enkevort was promoted to Generalwachtmeister and sent to the north where he fought under Spanish general Ottavio Piccolomini, fighting the French in the Spanish Netherlands and Picardy as part of the Franco-Spanish War (1635–59). Enkevort fought side by side with Johann von Werth, their friendship eased the tensions between the Bavarian and Imperial armies. In October 1637, Enkevort returned to the Rhineland where the Imperialists and their Liga allies pushed Bernhard out of his last stronghold in Alsace.