HistoryData
Historical ConflictRhineland

Operation Grenade

Operation Grenade secured the Roer river crossing for U.S. Ninth Army in February 1945, opening the Allied path into Germany west of the Rhine.

Duration & Scope

1945 ongoing

< 1 year

Estimated Total Casualties

113K

Key Facts

Roer crossing date
23 February 1945
German casualties (west Rhine)
~90,000 (incl. 50,000 POW)
Allied casualties
~23,000
Flooding delay
~2 weeks due to German dam release
Commanding U.S. general
Lt. Gen. William Hood Simpson

Strategic Narrative Overview

Planned for 9 February, the crossing was delayed when German forces opened the sluice gates of upstream Roer dams, flooding the river for nearly two weeks. Allied planners had anticipated this risk but were unable to capture the dams in time. Meanwhile, Hitler refused to allow German commander von Rundstedt to withdraw behind the Rhine, ordering the 15th Army and 1st Parachute Army to hold their positions, further weakening German defenses.

01 / The Origins

By early 1945, Allied forces were advancing toward Germany's western border. The U.S. Ninth Army, operating under Field Marshal Bernard Montgomery's 21st Army Group, was tasked with crossing the Roer River between Roermond and Düren. The operation was designed to coordinate with Operation Veritable, in which the Canadian First Army pushed south from Nijmegen, together forming a pincer movement to clear German forces west of the Rhine.

03 / The Outcome

The Ninth Army successfully crossed the Roer on 23 February 1945. Combined operations Veritable, Blockbuster, and Grenade resulted in approximately 90,000 German casualties west of the Rhine, with over 50,000 taken prisoner. Allied losses totaled around 23,000. The operation effectively cleared German resistance west of the Rhine and marked the beginning of the Allied invasion of Germany proper.

Belligerents & Mobilization Analysis

Side A

2 belligerents

U.S. Ninth Army (21st Army Group)Canadian First Army
Estimated Casualties~23K
Key Commanders

William Hood Simpson, Bernard Montgomery, Harry Crerar.

Side B

2 belligerents

German 15th ArmyGerman 1st Parachute Army
Key Commanders

Gerd von Rundstedt, Gustav-Adolf von Zangen, Alfred Schlemm.

Total Casualties (all sides)
113,000
Outcome
Allied victory; German forces west of the Rhine destroyed or captured; path into Germany opened

Kinetic Engagement Axis

Major engagements timeline (1945–present)Timeline of major military engagements plotted chronologically.1945present1945Roer River Cross…Allied

Scroll horizontally to view full axis. Events plotted relatively.

Side A victorySide B victoryInconclusiveDecisive / turning point

Location

Map of GermanyMap of GermanyGermany