Operation Queen was an American operation during World War II on the Western Front at the German Siegfried Line.

The operation was aimed against the River Roer as a staging point for a subsequent thrust over the river to the Rhine into Germany. It was conducted by the First and Ninth U.S. Armies.

The offensive commenced on 16 November 1944 with one of the heaviest Allied tactical bombings of the war. However, the Allied advance was unexpectedly slow, against heavy German resistance, especially in the Hürtgen Forest through which the main thrust of the offensive was carried out. By mid-December, the Allies finally reached the Roer and tried to capture its important dams, when the Germans launched their own offensive, dubbed Wacht am Rhein. The ensuing Battle of the Bulge led to the immediate cessation of Allied offensive efforts into Germany until February 1945.

In June 1944, the Allies conducted the invasion in Northern France and opened a new front. After the Allied breakout from Normandy, the German Wehrmacht was involved in a string of disastrous battles in July and August, most notably the Falaise pocket. Following those events, the German defense in northern and western France disintegrated, leading to a hasty retreat of the German forces. The rapid Allied advance together with the ongoing march of the Red Army in the east led the Allied High command to believe that the Wehrmacht was about to collapse and total victory could be achieved by Christmas 1944. The Allies, therefore, launched a high-risk plan for a direct thrust through the Netherlands into Germany, called Operation Market Garden. This overly ambitious plan failed, as the Wehrmacht was able to reorganize itself and consolidate its strength. By mid-September, the Allied advance abruptly ended, as the Allies suffered from a logistics crisis, outrunning their supply lines. This gave the Germans further time to prepare for the upcoming Allied offensives. The Germans now could man the fortifications of the Westwall (Siegfried Line), although its old bunkers were more symbolic than a real obstacle for the Allies.

In the north in Belgium, the Allies were still involved in the Battle of the Scheldt, while in the south in France the Lorraine Campaign was still ongoing. In the center, the Battle of Aachen was fought from 2–21 October at the German border. The heavy German resistance upset Allied plans for a fast resumption of the rapid advance. As preparation for Operation Queen, a preliminary offensive into the Hürtgen Forest had to be carried out, to secure the flanks against a possible German counterattack out of the forest. The goal was to clear a pathway to the important road junction at Düren, to gain a respectable starting position for Queen. The 9th Infantry Division was already engaged in the forest since September, so only moderate German resistance was expected. On 2 November, three days before the anticipated start of Operation Queen, the offensive against the town of Schmidt was launched by the 28th Division against the German 275th Division. The town was captured, but the Germans reacted swiftly by reallocating forces of the 89th Infantry Division and mobile reserves from the 116th Panzer Division, which drove the Allies out of the town, transforming the battle into a bloody stalemate.

The Allied High Command planned a large offensive in the area of the Ninth U.S. Army together with the First U.S. Army and parts of the British 2nd Army against the Roer River, intending to establish bridgeheads at Linnich, Jülich and Düren. The First Army – already stationed near the Hürtgen Forest – had to carry out the main effort through the Hürtgen Forest toward the Roer. The Ninth Army had to advance north of the forest through the Roer plains. The British XXX Corps – together with units from the U.S. XIII Corps – had to reduce the Geilenkirchen salient in the north in a different operation named Operation Clipper. The long term target after the Roer was crossed was to reach the Rhine and establish bridgeheads at Krefeld and Düsseldorf to secure further advances inside Germany after the winter. A great number of American and British strategic bombers were to conduct a series of tactical assaults in the area to cut supply lines and destroy enemy infrastructure, and also to attack the enemy defenders inside their positions. The entire operation was codenamed Queen. The 8th U.S. Air Force was to bomb the fortifications around Eschweiler and Aldenhoven, while the medium bombers of the 9th Air Force were assigned to the second line of defense around Jülich and Langerwehe. At the same time, the RAF Bomber Command was to hit the traffic centres of Jülich and Düren hard; the smaller towns of Heinsberg, Erkelenz and Hückelhoven were designated as secondary targets.

Initially, the starting date of the offensive was set for 5 November, later 10 November, but because of bad weather it was delayed until 16 November. The ground offensive was to begin immediately after the air raids, allowing the defenders no time to reestablish fortifications, supply routes and communications.

German planning was entirely different. Running out of strategic options, the Wehrmacht planned an all-out counteroffensive in the West, codenamed Wacht am Rhein. The first draft of the plan was already completed in secret in October 1944 and was aimed against the Ardennes, mirroring the successful campaign in 1940 against France. The plan required for the best divisions of the Wehrmacht to be held back from the autumn fighting, to gain time to build them up for the planned offensive. For the successful execution of the plan, the holding of the Roer river line was deemed as absolutely important, to prevent the Allies from a flanking attack. The German plan for the November–December Campaign was, therefore, to hold the Roer river line with a minimum of available forces until the Ardennes Offensive could be launched.