Cape Matapan — Cunningham against Iachino

In late March 1941, the Italian navy sortied from its bases to intercept the British convoys carrying troops to Greece. Admiral Angelo Iachino put to sea with the fast battleship Vittorio Veneto, heavy cruisers and destroyers, hoping to strike a decisive blow in the Eastern Mediterranean.

But at Bletchley Park, the Italian naval Enigma code had just been broken. Admiral Andrew Cunningham, at Alexandria, therefore knew of Iachino's sortie in advance. To avoid betraying this source, he had the area overflown by a reconnaissance aircraft that 'discovered' the Italian squadron, then put to sea with three battleships, the carrier Formidable and destroyers, while a light squadron served as bait.

Cunningham had to decide how to exploit this exceptional advantage: fight a classic daylight gun action, in which the fast Italian battleships might slip away; use naval aviation to slow the enemy down then catch him; or attempt the rare audacity of a night engagement, in which the Royal Navy, equipped with radar, held a decisive trump but ran the risk of confusion and friendly fire.