High Quality Content by WIKIPEDIA articles! The Nachtigall Battalion (German: Bataillon Ukrainische Gruppe Nachtigall), officially known as Special Group Nachtigall, was the subunit under command of the Abwehr special operation unit Lehrregiment "Brandenburg" z.b.V. 800. Along with the Roland Battalion it was one of two military units formed February 25, 1941 by head of the Abwehr Wilhelm Franz Canaris, which sanctioned the creation of the "Ukrainian Legion" under German command. It was manned primarily by occupied Poland citizens of Ukrainian ethnicity directed to unit by Bandera`s OUN orders .