Operation Diadem order of battle

Operation Diadem order of battle is a listing of the significant formations that were involved in the fighting on the Winter Line and at the Anzio bridgehead south of Rome during Operation Diadem in May - June 1944 which resulted in the Allied breakthrough at Cassino and the breakout at Anzio leading to the capture of Rome.

Allied Armies in Italy

 * C-in-C: General Sir Harold Alexander
 * Chief of Staff: Lieutenant-General Sir John Harding

U.S. Fifth Army
Commander:
 * Lieutenant-General Mark Wayne Clark

U.S. VI Corps (at Anzio)

 * Major-General Lucian K. Truscott
 * U.S. 3rd Infantry Division (Brigadier General John W. O'Daniel) until 25 May 1944
 * British 1st Infantry Division (Major-General John Hawkesworth)
 * U.S. 45th Infantry Division (Major General William W. Eagles)
 * U.S. 1st Armored Division (Major General Ernest N. Harmon)
 * U.S. 34th Infantry Division (Major General Charles W. Ryder)
 * U.S. 36th Infantry Division (Major General Fred Walker) (from 18 May 1944)
 * British 5th Infantry Division (Major-General Philip G.S. Gregson-Ellis)
 * First Special Service Force (3 regiments of two battalions each) (Brigadier General Robert T. Frederick)

U.S. II Corps (on the Winter Line)

 * Major-General Geoffrey Keyes
 * U.S. 88th Infantry Division (Major-General John E. Sloan
 * U.S. 85th Infantry Division (Major-General John B. Coulter)
 * 1st U.S. Armored Group (three tank battalions)
 * U.S. 3rd Infantry Division (Brigadier John W. O'Daniel) (from 25 May)

French Expeditionary Corps (on the Winter Line)

 * General Alphonse Juin
 * 3rd Algerian Infantry Division (Major-General Joseph de Goiselard de Monsabert)
 * 4th Moroccan Mountain Division (Major-General François Sevez )
 * 2nd Moroccan Infantry Division (Major-General André W. Dody)
 * 1st Motorised Infantry Division (1st Free French Division) (Major-General Diego Brosset)
 * Command of Moroccan Goumiers (Three Groups of Tabors each comprising three tabors of 500 to 800 men) (Brigadier-General Augustin Guillaume)
 * Corps Troops
 * 7th and 8th Regiments Chasseurs d'Afrique. (M10 tank destroyers)
 * Levant Artillery Regiment
 * 64th African Artillery Regiment
 * Marine Artillery group (two batteries)

Army Reserve

 * H.Q. U.S. IV Corps
 * U.S. 36th Infantry Division (Major-General Fred Walker) (from 18 May 1944)

British 8th Army (on the Winter Line)
Commander:
 * Lieutenant-General Sir Oliver Leese

XIII Corps

 * Lieutenant-General Sidney Kirkman
 * British 4th Infantry Division (Major-General Dudley Ward)
 * British 6th Armoured Division (Major-General Vivian Evelegh)
 * Indian 8th Infantry Division (Major-General Dudley Russell)
 * British 78th Infantry Division (Major-General Charles Keightley)
 * Canadian 1st Armoured Brigade (Brigadier W. C. Murphy)

Canadian I Corps

 * Lieutenant-General E. L. M. Burns
 * Canadian 1st Infantry Division (Major-General Chris Vokes)
 * Canadian 5th Armoured Division (Major-General Bert Hoffmeister)
 * British 25th Army Tank Brigade (Brigadier J.N. Tetley)

Polish II Corps

 * Lieutenant-General Władysław Anders
 * Polish 3rd Carpathian Rifle Division (Major-General Bolesław Bronisław Duch)
 * Polish 5th Kresowa Infantry Division (Major-General Nikodem Sulik)
 * Polish 2nd Armoured Brigade (Brigadier-General Bronislaw Rakowski)

British X Corps

 * Lieutenant-General Sir Richard McCreery
 * New Zealand 2nd Division (Lieutenant-General Sir Bernard Freyberg)
 * British 24th Guards Brigade (Brigadier A.F.L. Clive)
 * British 2nd Parachute Brigade (Brigadier C.H.V. Pritchard)
 * 12th South African Motorised Brigade (Brigadier R.J. Palmer)
 * Italian Corps of Liberation (Six battalions and a regiment of artillery) (General Umberto Utili)

Army Reserve

 * South African 6th Armoured Division (Major-General Evered Poole)

British V Corps (On the Adriatic front in a holding role directly under A.A.I.)

 * Lieutenant-General Charles Allfrey
 * Indian 4th Infantry Division (Major-General Arthur Holworthy)
 * Indian 10th Infantry Division (Major-General Denys Reid)
 * British 23rd Armoured Brigade (Brigadier R.H.E. Arkwright)

German Army Group C
Commander:
 * Field Marshal Albert Kesselring

Army Group Reserve

 * German 92nd Infantry Division (Major-General Werner Goeritz) (Tiber Coastal Command )
 * Hermann Göring Panzer Division (Brigadier-General Wilhelm Schmalz) (in OKW Reserve )
 * German 29th Panzergrenadier Division (Lieutenant-General Walter Fries)
 * German 26th Panzer Division (Lieutenant-General Smilo Freiherr von Lüttwitz)
 * German 90th Panzergrenadier Division (Major-General Ernst-Günther Baade)

German Fourteenth Army (at Anzio)

 * Commander: Lieutenant-General Eberhard von Mackensen (until end May 1944, then under direct command of Kesselring)

German I Parachute Corps

 * Lieutenant-General Alfred Schlemm
 * German 4th Parachute Division (Major-General Heinrich Trettner)
 * 65th Infantry Division (Major-General Hellmuth Pfeifer)
 * 3rd Panzergrenadier Division (Brigadier-General Hans Hecker to 1 June then Major-General Hans-Günther von Rost to 25 June then Major-General Walter Denkert)

German LXXVI Panzer Corps

 * Lieutenant-General Traugott Herr
 * German 362nd Infantry Division (Major-General Heinz Greiner)
 * German 715th Infantry Division (Major-General Hans-Georg Hildebrandt)

German Tenth Army (on the Winter Line)

 * Commander: General Heinrich von Vietinghoff

XIV Panzer Corps

 * Lieutenant-General Frido von Senger und Etterlin (on leave 17 April to 17 May during which time Lieutenant-General Otto Hartmann )
 * 15th Panzergrenadier Division (Major-General Rudolf Sperl)
 * German 71st Infantry Division (Major-General Wilhelm Raapke)
 * German 94th Infantry Division (Major-General Bernhard Steinmetz)

LI Mountain Corps

 * Lieutenant-General Valentin Feurstein
 * German 44th Reichsgrenadier Division Hoch und Deutschchmeister (Major-General Bruno Ortner)
 * German 1st Parachute Division (Lieutenant-General Richard Heidrich)
 * German 114th Jäger Division (Major-General Alexander Bourquin to 19 May 1944 then Major-General Hans Boelsen)
 * German 5th Mountain Division (Major-General Max-Günther Schrank)

Korpsgruppe Hauck (on Adriatic front in holding role)

 * Major-General Friedrich-Wilhelm Hauck
 * German 305th Infantry Division (Lieutenant-General Friedrich-Wilhelm Hauck)
 * German 334th Infantry Division (Major-General Hellmuth Böhlke)

Armeegruppe von Zangen (in northern Italy)

 * Commander: Lieutenant-General Gustav von Zangen

LXXV Corps

 * Lieutenant-General Anton Dostler
 * 356th Infantry Division (Major-General Egon von Neindorff until 15 May then Major-General Karl Faulenbach)
 * 162nd Turkoman Division (Major-General Oskar von Niedermayer)

Corps Witthöft (Eastern sub-Alpine region)

 * Lieutenant-General Joachim Witthöft
 * 188th Mountain Division (Major-General Hans von Hößlin)
 * 278th Infantry Division (elements) (Major-General Harry Hoppe)

Corps Kübler (Adriatic coastal region)

 * Lieutenant-General Ludwig Kübler
 * 278th Infantry Division (most of) (Major-General Harry Hoppe)