Top Photo: 3rd U.S. Army soldiers guard German prisoners in the public square at Kaiserslautern, Germany. March 21, 1945. Signal Corps Archive.

In March 1945, the Western Allies broke through the winter barriers that blocked their advance into the heart of Germany and were poised to cross the Rhine, cut out the heart of Germany’s industry in the Ruhr valley, and advance to meet the Soviet armies then closing in on Berlin. To the north, the combined Anglo-American operations of Veritable and Grenade gave British Field Marshal Sir Bernard Montgomery’s 21st Army Group the long-sought jumping-off positions for a spectacular combined airborne and amphibious operation to cross the lower Rhine, executed on March 24 as Operations Varsity and Plunder, respectively. 

Just south, the American 12th Army Group’s Operation Lumberjack brought the US First Army to the Rhine, and the unexpected coup at the Ludendorff Bridge near Remagen on March 7 made First Army the first Allied force to seize positions on the river’s east bank. Lumberjack also provided a portion of General George S. Patton’s Third Army frontage along the entire lower reaches of the Moselle River. As First Army curled north to envelop the Ruhr Vally from the south, it required flank protection on its right, and some of Patton’s forces were still almost 60 miles from the Rhine near Trier, having spent the previous two months recapturing territory taken in the Battle of the Bulge and then pushing through the difficult terrain of the Eifel and the strong German defensive belts known as the Siegfried Line. 

To the south, the combined Franco-American 6th Army Group had spent most of February clearing out the Colmar Pocket, allowing the French First Army to close up the Rhine from the Swiss border to the German frontier. But the US Seventh Army still faced the formidable Westwall defenses running southeast from the Saarland to the Rhine. This left a massive German salient on the western bank of the Rhine, stretching from Koblenz up the Moselle Valley to near Trier, and then along the Saar Valley and the French-German border back to the Rhine near Karlsruhe. To get Patton’s Third Army across the Rhine and in position to both protect First Army’s flank and exploit any openings into central and southern Germany, Allied Supreme Commander General Dwight D. Eisenhower ordered the Third and Seventh Armies to clear out the last German forces in the Rhineland. The resulting plan, code-named Operation Undertone, envisioned a converging attack, placing overwhelming pressure on the German defenders. A breakthrough by either American field army would threaten the rear of the defenders facing the other, and the Germans had insufficient forces to take advantage of their interior lines to shift forces to any threatened point.     

German defenders could clearly see the writing on the wall, as Soviet forces broke through and entered Germany from the east. As the last army group still west of the Rhine, SS General Paul Hausser feared his Army Group G would be surrounded and cut off, or afforded the opportunity to reach the temporary security of the Rhine’s eastern bank. On paper, he had two field armies—the Seventh in the north defending along the Moselle and the First in the south, still holding positions along the Saar River and in front of the vaunted Siegfried Line. But closer examination revealed that the continued attrition, combined with the heavy losses sustained in the Bulge and withdrawals for the east, had left a hollow force. Most of the divisions were titled Volksgrenadiers but were made up of older men, young boys, and service troops repurposed from elsewhere in the once-vaunted Wehrmacht. The few mechanized divisions, including the 17th SS Panzergrenadier Division holding positions around Pirmasens in the south, had only a handful of tanks left and frequently no fuel to move them. These forces could defend behind the concrete “dragon’s teeth” antitank barriers and man pillboxes until reduced or out of ammunition, but they could not hope to offer anything resembling the strong, active defenses that had stalled the Allies the previous fall. 

The Rhineland Campaign: Operations between March 11-21, 1945. United States Military Academy

The American armies, in contrast, were hitting the peak of their strength. Losses in personnel in the Bulge had been replaced, in some places with the first integrated units of Black soldiers serving in separate platoons in the same formations as white soldiers. Equipment losses had been replenished as well, with equipment and petroleum pouring through secure and rehabilitated ports such as Antwerp and Marseilles. A year of experience in integrating infantry, armor, artillery, and air support made the American forces adept at overwhelming or bypassing resistance and exploiting weak spots in the German lines, of which there were many. Patton’s Third Army was organized into three corps of 12 divisions, including four armored, totaling over 320,000 men. General Alexander Patch’s Seventh Army also contained three experienced corps, with 14 divisions, including three armored, and over 350,000 men. The mismatch on paper between the German and American forces was obvious, but soldiers still had to advance across the muddy ground and take the positions from Germans protecting their homeland.

Anxious to reach the river, and especially to get across the Rhine ahead of his old rival Montgomery, whose characteristic set-piece operation had been scheduled for March 26, Patton jumped off on March 12 near Koblenz. The Moselle Valley was a significant obstacle, if strongly defended, with steep ridges covered with open vineyards heading down to a wide, deep, meandering channel. But the Germans lacked the firepower to interdict the approach or to defend every one of the various switchbacks and meanders, and Patton’s infantry crossed with relative ease, rapidly opening corridors for his armored forces to exploit. At the point of the apex near Trier, XX Corps was already through the prepared defenses south of Trier and broke out to the east, with the 10th Armored Division racing through St. Wendel for Kaiserslautern, to cut the autobahn leading through the low defile in the Haardt Mountains. With the city and the evacuation route to the east blocked, German forces around Saarbrücken would be cut off, encouraging them to abandon their efforts against Seventh Army and join the exodus toward the Rhine.

Seventh Army still had a difficult task, as the German fortifications in the Pfalzwald slowed attackers. To help the offensive, Allied medium bombers took advantage of unusually clear spring weather on March 15 to virtually level the towns of Pirmasens and Zweibrücken, important communications hubs just behind the front lines. The attacks cut the flow of reinforcements and supplies to the front but also killed hundreds of German civilians who had made it to less than two months from the end of the war. Determined efforts by the 45th Infantry Division and other American units heading up the Blies River just east of Saarbrücken finally turned the German positions. As Patton’s armor raced down from the north, German commanders finally began ignoring Hitler’s orders to hold every inch of German soil and began an orderly retreat for the bridges still spanning the Rhine.

As the German columns clogged the roads to the east, they became easy prey for Allied aircraft, especially the fighter bombers enjoying virtually uninterrupted aerial superiority over the battlefield. A futile counterattack by the Luftwaffe on March 20 cost irreplaceable aircraft and pilots but achieved little, while American P-47s savaged the German convoys winding along the bottom of the steep valleys of the Haardt Mountains. In several places, well-timed attacks halted progress, allowing planes to shoot up vehicles lined up bumper to bumper. One attack near Hauenstein virtually destroyed the retreating 17th SS Division, and American engineers working to clear the road simply pushed the charred debris into a bomb crater, where it remained until 2002, when it was unearthed during a road construction project.   Similar attacks at the exits from the Pfalzwald near Neustadt and Bad Dürkheim inflicted more damage on the retreating Germans, forcing them to abandon equipment that could then not be used to build up any substantial defenses across the Rhine. 

The 10th Armored Division reached Kaiserslautern on March 20, and the 80th Infantry Division, following close on its heels, captured 275 prisoners in the city, marking the beginning of a long US military presence in the area that continues to this day. But the 80th’s stay was brief, and by March 28 they were in Mainz, headed across the river to join other Third Army elements that had crossed on March 22, two days ahead of Montgomery. Patton’s forces fanned out across central and southern Germany, fighting a last battle against the fanatical Nazi defenders at Nuremburg, liberating the massive concentration camp near Munich at Dachau, and reaching the Czech and Austrian borders by early May. At a cost of 5,220 casualties in the Third Army, including 681 killed, and another 12,000 in the Seventh Army, Operation Undertone had cleared almost 5,000 square miles of German territory and killed or captured over 100,000 German soldiers. Long overshadowed by Montgomery’s elaborate operation at Wesel and the First Army’s coup at Remagen, the combined efforts of the Third and Seventh Armies put powerful forces deep into the heart of Germany and demonstrated clearly to the German people that National Socialism was dead.