British Forces

15th Cruiser Div.
CL        Cleopatra  Capt Guy Grantham
   Rear-Admiral Philip Vian (Commanding)
CL        Dido          Capt H.W. McCall
CL        Euryalus    Capt Eric Bush
CLAA  Carlisle      Capt D.M.L. Neame

Force K
CL        Penelope   Capt A.D. Nicholl
DD       Legion        Cdr R.F. Jessel
 

14th Destroyer Flotilla
    Capt. A. L. Poland—Division Commander
DD     Jervis
DD     Kipling
DD     Kelvin
DD     Kingston

22nd DD Flotilla
DD     Sikh
    Capt. St. J. A. Micklethwaite—Div. Com.
DD     Hero            Cdr R.L. Fisher
DD     Lively
DD     Havock
DD     Hasty           Cdr H.R. Graham
DD     Zulu

5th Destroyer Flotilla (Hunt Class Escort Destroyers)
DD     Southwold   Cdr C.T. Jellicoe
DD     Beaufort
DD     Dulverton
DD     Hurworth
DD     Avon Vale
DD     Eridge
DD     Heythrop

Convoy MW.10
Aux.    Breconshire
    Capt C.A.G. Hutchison    (convoy commodore)
MS     Clan Campbell
MS     Pampas
MS     Talabot     (Norwegian)

Italian Forces
BB Littorio
   Vice-Admiral Angelo Iachino—Fleet Com.

3rd Cruiser Division
CA Gorizia
    Rear-Admiral Angelo Parona—Div. Com.
CA Trento
CL  Bande Nere

11th Destroyer Flotilla
DD Ascari
DD Aviere
DD Oriani
DD Grecale

13th Destroyer Flotilla
DD Alpino
DD Bersagliere
DD Fuciliere
DD Lanciere

Sources:
1. The Naval War in the Mediterranean 1940-1943 by J. Greene & A. Massignani
2. Chronology of the War at Sea 1939-1945 by J. Rohwer & G. Hummelchen
3. The Italian Navy in WWII by A. Bragadin
4. Sea Battles In Close Up WW2 Vol2 by Eric Grove
5. Battleship, Cruiser, Destroyer by Gregory Haines and Cdr B.R. Coward.