Operation Pegasus launched Operation Market Garden, an attempt by the British 2nd Army to bypass the Siegfried Line and advance into the Ruhr, Germany’s industrial heartland. The operation required the First Allied Airborne Army to seize several bridges over rivers and canals in the Netherlands, allowing ground forces to advance and cross the Lower Rhine at Arnhem. The 1st British Airborne Division dropped onto Arnhem on 17 September. They encountered far greater resistance than had been expected and only a small force were able to reach Arnhem road bridge. XXX Corps ground advance became delayed and without reinforcement this small force under
Operation Market Garden for air supply. Montgomery initially suggested "Operation Comet", a limited airborne "coup de main" operation that was to be launched on 2 September 1944. Comet envisioned using the British 1st Airborne Division, along with the Polish 1st Independent Parachute Brigade, to secure several bridges over the Rhine River to aid the Allied advance into the North German Plain. The Divisional Headquarters for the British 1st Airborne Division, with the 1st Airlanding Brigade and the Polish 1st Independent Parachute Brigade were to land at Nijmegen, the British 1st Parachute Brigade was to land at Arnhem, and the British 4th Parachute Brigade