'Union II' was an Allied special forces operation to parachute an eight-man US, French and British team under Major Peter J. Ortiz (with another five men the only members of the into US Marine Corps to see combat in the European theatre) into the Haute Savoie area of German-occupied France to establish liaison with the local resistance forces, the Maquis des Glières (1 August 1944 onward).

The operation also included a large weapons and equipment drop at the Col de Saisies, and the airdrops were instrumental in the rebuilding of the Maquis des Glières, which had been hard hit earlier in the same year by the German 'Hoch-Savoyen' offensive of of 26/30 March.