1916: The largest-ever battleship action took place in the North Sea off Jutland. 151 British warships, including 28 Dreadnought battleships and nine battlecruisers, fought 96 German warships, including 22 battleships and 5 battlecruisers.

Vice Admiral Scheer, commanding the German High Seas Fleet, hoped to isolate and destroy a part of the Royal Navy's much superior Grand Fleet. To this end, he took the High Seas Fleet out for a sweep towards the Skagerrak, whilst U-boats lurked off the main Royal Navy bases in the hope of ambushing the British ships as they put to sea. Signals intelligence ensured that the Royal Navy knew that the Germans planned an operation - and indeed the Grand Fleet was actually able to sail several hours ahead of the Germans - but faulty consideration of the information misled the Admiralty into believing the German sortie was by Hipper's battlecruisers only. Vice Admiral Beatty's Battlecruiser Fleet encountered Hipper's battlecruisers at 1420 on 31 May. Outnumbered, Hipper withdrew, luring Beatty towards the main German fleet. During the battlecruiser duel, both Indefatigable and Queen Mary were lost to catastrophic explosions, after flash from shell hits penetrating their gun turrets spread to the magazines. 1,266 men died aboard Queen Mary, 20 survived. 1,017 died aboard Indefatigable: only two men survived to be rescued by a German destroyer hours later.

Upon sighting the Scheer's main force, Beatty turned and ran back for the Grand Fleet, in turn luring Scheer towards Admiral Jellicoe's overwhelmingly superior force. The 5th Battle Squadron, comprising four of the Queen Elizabeth class Dreadnoughts, then the world's fastest and most powerful battleships, covered the withdrawal. The weather was, however, deterioriating, particularly visibility. Scheer's battleships blundered into their worst fear: the full Grand Fleet deployed in line of battle. Jellicoe's battleships inflicted considerable damage on the leading German ships before Scheer skilfully turned his entire force around to run for home. However, a third British battlecruiser, HMS Invincible, was lost to another catastrophic explosion, as was the armoured cruiser HMS Defence. The entire crew of 903 perished aboard Defence, whilst only six men survived from Invincible's complement of 1,032. Another armoured cruiser, Warrior, later sank from the battering she had received.

During the night, the two fleets brushed past each other, and confused fighting cost the Royal Navy another armoured cruiser, Black Prince, lost with all 857 hands. British destroyers succeeded in torpedoing the elderly battleship Pommern which blew up with her entire crew of 844. The Germans also lost Hipper's flagship, the powerful battlecruiser Lutzow, which finally sank from massive damage sustained earlier in the day. Another battlecruiser, Seydlitz, only just made it back to port, with over 5,000 tons of water in her. Jutland cost the Germans 2,551 men killed, and the loss of a battlecruiser, battleship, four light cruisers and five destroyers. The Royal Navy lost 6,094 men, three battlecruisers, three armoured cruisers and eight destroyers. However, the battle proved a victory for the Royal Navy: the Germans were well aware that, if visibility had been better, the High Seas Fleet might have suffered crippling losses, and did not dare challenge the Grand Fleet again.

Four Victoria Crosses were won that day. Commander Jones, Boy Seaman Cornwall - aged 16 - and Major Harvey, Royal Marine Light Infantry, were each awarded the medal posthumously for acts of heroism despite fatal injuries, whilst Commander Bingham received the VC for leading a destroyer attack on the main German battle fleet.

1940: On the outskirts of Dunkirk, Captain Ervine-Andrews of the East Lancashire Regiment commanded part of the rearguard. Despite being badly out-numbered, he led a team of volunteers in an attack across a canal, inflicting heavy losses on the Germans, before withdrawing: he and his men waded down the canal for a mile, up to their necks in water, to reach safety. Ervine-Andrews was awarded the Victoria Cross.

Meanwhile on the beaches, the fog which had offered protection from air attack the previous day began to lift. Mid-day saw the Luftwaffe return to the attack, another large transport being sunk, with several others damaged. The Germans lost seventeen aircraft, while the RAF and Fleet Air Arm, conducting both defensive patrols and bombing attacks on troop concentrations pressing in on the pocket, lost twenty-eight.

1942: Three Japanese midget submarines raided Sydney Harbour. HMAS Kuttabul, a depot ship, was damaged by a torpedo, but all three of the Japanese submarines were sunk.