Tirpitz was the mascot of HMS Glasgow during the First World War. The pig had originally been kept on board the German cruiser SMS Dresden until she sank in March 1915. Tirpitz was abandoned with the ship, but managed to escape and swim away from the sinking vessel. She was spotted by the crew of the nearby HMS Glasgow and one of the sailors jumped in to rescue the frightened animal, nearly drowning in the process. The crew awarded Tirpitz a fake Iron Cross – a German military honour – for remaining on board the sinking Dresden after the rest of her crew had left. Tirpitz served as Glasgow's mascot until 1916, when she was retired to the Whale Island Gunnery School near Portsmouth. She was auctioned off for pork in 1919, raising £1,785 for the British Red Cross. Tirpitz's head was mounted and given to the Imperial War Museum in London, where it remains on display.

Edith Cavell was an English nurse who helped over 200 Allied soldiers escape German-occupied Belgium during the First World War. Cavell would sometimes take Jack (pictured here on the right) on walks, providing cover for the escaping soldiers as they travelled to meet their guides. She was caught, tried and convicted of treason, and was executed by firing squad on 12 October 1915. Jack was rescued by Princess Mary de Croy after Cavell's execution and taken to the family's country estate in Belgium, where he remained until his death in 1923. His embalmed body was sent to the Norfolk branch of the Red Cross. Jack was on display at IWM London until 2013.

Gustav was one of the RAF's messenger pigeons during the Second World War and one of six birds given to Reuters news correspondent Montagu Taylor ahead of D-Day. On 6 June 1944 Gustav carried back the first news from the D-Day landings in Normandy. He flew more than 150 miles (241 km) – from the northern coast of France to his loft near Portsmouth – in just over 5 hours to deliver this message: 'We are just 20 miles or so off the beaches. First assault troops landed 0750. Signal says no interference from enemy gunfire on beach...Steaming steadily in formation. Lightnings, typhoons, fortresses crossing since 0545. No enemy aircraft seen'. Gustav was awarded the Dickin Medal in September 1944. He is one of 32 pigeons – more than any other species – that have received the award.

Rip was a stray dog adopted by the Poplar ARP (Air Raid Precautions) in east London during the Second World War. During the Blitz, he helped locate people and animals buried in the debris after an air raid. In this photograph, taken on 5 August 1941, Rip searches the rubble for survivors after an air raid in Poplar, east London.

Jet was an Alsatian trained as a search and rescue dog during the Second World War. He and his handler, Corporal Wardle, were responsible for recovering 150 people from buildings destroyed in German air raids. On one occasion, Jet located a woman buried in the debris of a bombed-out hotel in London, and refused to move for 12 hours while rescuers tried to reach her. Jet was awarded the Dickin Medal in January 1945.

Wojtek the 'Soldier Bear' was the pet mascot of the 22nd Transport Artillery Supply Company, Polish II Corps during the Second World War. The Syrian brown bear was adopted as a cub by Polish troops as they passed through Iran on their way to a posting in the Middle East. Wojtek, meaning 'little one', weighed around 18 stone (250lb/113kg) and grew to over six feet tall. But he was extremely tame and comfortable in human company, often wrestling or play-fighting with the men. In 1943, the unit were posted to Italy and Wojtek was enlisted so that he could accompany them - he was even assigned a service number and given the rank of Private. During the fierce fighting for Monte Cassino, Wojtek helped with the vital task of keeping front-line troops supplied by carrying heavy shells and boxes of ammunition. The image of Wojtek carrying shells was later incorporated into the company’s insignia. After the war, Wojtek travelled with the unit to Scotland, where he eventually found a home at Edinburgh Zoo until his death in 1963.

Judy was a purebred English pointer who had been adopted as a mascot by the Royal Navy. When her ship, HMS Grasshopper, was torpedoed during the Second World War, Judy and the crew were captured by the Japanese and held as prisoners of war (POWs). Judy was adopted by Leading Aircraftsman Frank Williams, who shared his meagre rations with her throughout their imprisonment. Williams even managed, in an attempt to safeguard her life, to have Judy officially registered as a POW. Judy was extremely protective of her fellow prisoners. She would bark and growl to distract guards as they beat POWs, and often left the camp to bring back food for the starving prisoners. Judy and Williams were liberated in 1945. Judy was awarded the Dickin Medal the following year for 'magnificent courage and endurance in Japanese prison camps, which helped to maintain morale among her fellow prisoners and also for saving many lives through her intelligence and watchfulness'.