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Crimean War (1853–56) -

Troops celebrate the festive season with Christmas dinner in December 1854 during the Siege of Sevastopol. The battle was a major operation during the Crimean War.

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American Civil War (1861–1865) -

During a lull in fighting, Union and Confederate troops toast each from opposite sides of a stream at Christmastime during the American Civil War.

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American Civil War (1861–1865) -

Troops stationed at a Union camp welcome Santa Claus into their ranks during Christmas 1863.

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American Civil War (1861–1865) -

A Christmas gift basket is emptied of its seasonal goodies by delighted Union troops at Christmastime. Pairs of warm, dry socks number among the most desired presents.

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Second Boer War (1899–1902) -

British soldiers reading their Christmas mail while in camp at De Aar in South Africa during the Second Boer War.

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Second Boer War (1899–1902) -

Christmas presents arrive from home in a hamper for British troops stationed at Modder River in 1899. The Battle of Modder River resulted in a British victory, but at the cost of many lives.

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Russo-Japanese War (1904–1905) -

Russian soldiers based near Mukden celebrating Christmas in frivolous style in December 1904. The Battle of Mukden began in February 1905 as one of the largest land battles to be fought before the First World War and the last and the most decisive major land battle of the Russo-Japanese conflict.

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First World War (1914–1918) -

The first Christmas of the First World War saw combatants from both sides celebrate the festive season as best they could. Here, German soldiers decorate a tree near the front lines.

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First World War (1914–1918) -

Christmas 1914 witnessed one of the most remarkable events of the entire conflict. On December 24, British and German troops ceased fire and met in No Man's Land to fraternize and exchange food and gifts (pictured). The impromptu get-together became known as the Christmas Truce. But this symbolic moment of peace was short lived. A few days later, those very same men were back in the trenches aiming their guns at each other.

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First World War (1914–1918) -

Sailors on the British Royal Navy destroyer HMS Mermaid sit down for a lavish lunch on Christmas Day 1916. The Royal Navy's flag, the White Ensign, acts as a tablecloth.

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First World War (1914–1918) -

Members of a German regiment catch up on their Christmas mail in a trench decorated with a Christmas tree in Belgium in 1915.

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First World War (1914–1918) -

Wounded German soldiers celebrate Christmas in hospital in 1916. Nurses serve as Santa's helpers, delivering parcels to their patients.

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First World War (1914–1918) -

After the war's end in December 1918, defeated but still armed front line troops gather in Berlin's Pariser Plazt, decorated with fir sprigs and flowers in a semblance of Christmas goodwill.

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Second World War (1939–1945) -

By December 1939, the Second World War had started. Christmas shopping in London took on a surreal edge as sandbags protected retail premises and other buildings. Here, members of the pubic window shop Selfridges during the first Christmas of the conflict.

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Second World War (1939–1945) -

German sailors bringing Christmas trees aboard a battle cruiser, anchored near Schleswig-Holstein in late 1939.

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Second World War (1939–1945) -

A couple attempt to get into the Christmas spirt by kissing under the mistletoe wearing gas masks in early 1940. Great Britain was on full alert as the Blitz, a German bombing campaign against the United Kingdom in 1940 and 1941, began in earnest.

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Second World War (1939–1945) -

Despite the constant fear of an air attack, Londoners did their best to follow a daily routine, including this Santa Claus delivering gifts wearing a steel Brodie helmet.

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Second World War (1939–1945) -

A young girl is pictured sleeping under Christmas decorations and stockings stuffed with treats in 1940. Santa Claus still visited British homes during the Second World War, but often left gifts for people celebrating in bomb shelters.

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Second World War (1939–1945) -

Hospitals sometimes served a double purpose, as illustrated by this 1942 photograph of wounded American servicemen recovering on a medical ward in England and helping to make toys to give to local children. A nurse lends a helping hand.

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Second World War (1939–1945) -

For some, Christmas 1942 was an horrific nightmare. In Stalingrad, Soviet forces pinned down the German 6th Army as it attempted to take the city. In one engagement, the Wehrmacht had intended to capture the Krasny Oktyabr ("Red October Factory") steel plant as a Christmas present for Adolf Hitler. Instead, they were forced into a retreat by the Russians, who held it for the duration of the conflict.

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Second World War (1939–1945) -

The crew of a German U-boat find a way of celebrating the festive season in the depths of winter by organizing a Christmas Eve dinner onboard their submarine.

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Second World War (1939–1945) -

The winter of 1944 in Europe was one of the harshest on record. In this image, US soldiers forget about the cold to receive Christmas mail and parcels from home after the American success in driving out the Nazis from La Gleize, in Belgium—one of the military engagements of the Battle of the Bulge.

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Second World War (1939–1945) -

In Burma (now Myanmar), American troops were celebrating Christmas in the heat of the jungle by holding an outdoor mass, guarded by a cannon.

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Korean War (1950–1953) -

Australian troops celebrate Christmas 1950 in a bitterly cold field camp during the conflict fought between North Korea and South Korea. North Korea was supported by China and the Soviet Union, while South Korea was propped up by the United States and allied countries.

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Vietnam War (1955–1975) -

An American machine gunner is no doubt thinking of home and loved ones as he reads a Christmas card during a tour of duty in Vietnam in 1967.

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Vietnam War (1955–1975) -

In a photograph taken December 25, 1967, two US soldiers enjoy some downtime next to a small artificial Christmas tree on their position at Hill 875 near Dak To, a month after the North Vietnamese Army had launched a massive assault on the area.

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Vietnam War (1955–1975) -

US troops, most of them in their early twenties, attend a Christmas mass at Cu Chi Base Camp northwest of Saigon in 1969.

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Gulf War (1990–1991) -

Santa hits the deck as a catapult and arresting gear officer onboard the USS Abraham Lincoln during Operation Southern Watch towards the end of the 1991 Gulf War.

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Iraq War (2003–2011) -

US Army Fourth Infantry Division personnel decorate a makeshift tree before Christmas dinner on December 25, 2003 in Samarra during the Iraq War.

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Iraq War (2003–2011) -

British servicemen sing hymns and carols during Christmas celebrations at the Shatt al-Arab camp in the southern Iraqi port city of Basra on December 25, 2008.

Sources: (History) (Britannica) (HistoryNet)

See also: The origins of popular Christmas traditions

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