(covers information from several alternate timelines)
The main combatants included the Allies (a number of nations, including the United States of America, the British Empire and Commonwealth, the Union of Soviet Socialist Republics, Australia, Belgium, Canada, China, France, Netherlands and Poland) and the Axis Powers (the Nazi-controlled state of Germany, Italy, and the Empire of Japan).
After Jonathan Archer restored a damaged timeline, several scenes from World War II, including German Heinkel He 111s and parachutists, could be seen in the time stream as the timeline realigned itself. (ENT: "Storm Front, Part II")
Initially assuming an official position of neutrality, the United States fully entered the conflict after a Japanese attack at Pearl Harbor. (TNG: "The Enemy"; VOY: "The 37's"; DS9: "Far Beyond the Stars")
According to Captain Jean-Luc Picard in the role of Dixon Hill, the Second World War, although disastrous, did end with the United States taking its place as a dominant world power, culturally influencing the second half of the 20th century. Additionally, the war was a catalyst of technological advancements; developments in rocketry and fission resonated on into the 24th century. (TNG: "Manhunt")
Impact & Legacy
While Hirogen under Alpha Karr were in control of the USS Voyager, one of the ship's holodecks was programmed with a holographic simulation of this timeframe, set in 1944, during an Allied invasion of Nazi-controlled territory in France. (VOY: "The Killing Game", "The Killing Game, Part II")
- "Today, the guns are silent. A great tragedy has ended. We have known the bitterness of defeat and the exultation of triumph, and from both we have learned there can be no turning back. We must go forward to preserve in peace what we've won in war."
Alternate timelines and realities
Temporal Cold War
- Main article: World War II (Temporal War)
In one alternate timeline, the Na'kuhl assisted Nazi Germany in its war effort. In this timeline, Vladimir Lenin had been assassinated in 1916 which allowed Germany to focus on its Western opponents, conquering Belgium, France and the Netherlands. The Nazis subsequently sent troops and conquered Britain, the Northeastern United States, and a part of Russia extending past Moscow as well as parts of Africa. The Nazis took over New York City after the US military ordered a hasty retreat to the Midwest, causing refugees to flood over the Brooklyn Bridge. (The Germans subsequently rolled over Flatbush Avenue in Brooklyn and took over Washington, DC.)
However, by 1944 this was described as Germany "stretching too far, too quickly." Resistance fighters constantly attacked German supply lines and the front lines were too thin. An American counterattack could – and later tried to – break through the front lines, when Captain Archer and Enterprise NX-01 showed up in New York City. The Germans also faced problems in their stronghold in Africa, while Russian forces attempted to retake Moscow.
Following the destruction of the Xindi weapon by the crew of Enterprise in 2154, Commander Tucker and Ensign Mayweather found themselves over San Francisco, being attacked by P-51 Mustangs, while Captain Archer was seen lying unconscious in a field hospital – under the observation of a Na'kuhl officer in a Nazi captain's uniform. Near the Brooklyn Bridge, Enterprise destroyed a temporal conduit whose construction had been overseen by Na'kuhl leader Vosk, thus closing this timeline and apparently preventing the Temporal War. This was one of the major campaigns of the Temporal Cold War. (ENT: "Storm Front", "Storm Front, Part II")
World War II and the Guardian of Forever
An alternate timeline also existed in which Germany won the Second World War, partly due to the delayed entry into the war by the United States. Another contributing factor to the German victory was the prevention of Edith Keeler's death by Doctor Leonard McCoy, who had traveled to the past from the 23rd century. Keeler was an anti-war activist whose activism, in the altered timeline, had persuaded the United States to stay out of the war long enough to ensure a Nazi victory.
In the altered reality, Edith Keeler eventually met with President Roosevelt, effectively organizing pacifist movements to ensure the United States did not join the Allies and contribute to the escalation of war. Without the US contributing to the efforts to fight the Axis Powers, Germany completed its heavy water molecular experiments, created an atomic bomb first in the new history, and used German V-2 rockets to launch numerous atomic bombs, effectively capturing the world. This timeline was averted when McCoy was followed through the Guardian of Forever time portal, by James T. Kirk and Spock, who prevented him from interfering in Keeler's death, restoring the "correct" version of history. (TOS: "The City on the Edge of Forever")
A very similar conflict, sharing the same weaponry such as the Stuka dive bomber, has been fought in the mirror universe. However, the exact details, nature or even outcome of that conflict remain unknown. (ENT: "In a Mirror, Darkly", "In a Mirror, Darkly, Part II", opening credits)
|Earth wars prior to the Federation|
|Crusades • American Revolution • American Civil War • World War I • World War II • Brush Wars • Earth Cold War • Eugenics Wars • World War III • Kzinti Wars • Xindi incident • Earth-Romulan War|
A large number of TOS writers, actors, producers and other production staff members served as veterans of the Second World War. Among these were Gene Roddenberry, James Doohan, DeForest Kelley, Mark Lenard, Matt Jefferies, Robert Justman, Joseph Pevney and Ralph Senensky. The exploits of the US Navy Aircraft carrier USS Enterprise inspired the name of Kirk's ship.
In TOS: "Bread and Circuses", Spock states that eleven million people died in World War II. This, however, severely contradicts current data, which places the death toll anywhere from a low of twenty million (if only military is counted) to a high of over seventy million (if military and civilians are counted). Most counts settle on around fifty million or so. 
Spock may have been referring solely to civilian casualties as a result of "slavery" and "despotism" rather than the total war itself. Eleven million is a number frequently given for civilian deaths solely from Nazi policies. This might explain a figure of six million that he gave for World War I, too, as that is about an average (slightly on the low side) estimate of civilian deaths out of a World War I total of about sixteen million.
World War II was mentioned in the shooting script of "The Way of the Warrior". In the scene, Miles O'Brien talks to Kira Nerys about his new holoprogram based on the Battle of Britain. Major Kira was not familiar with the war.
According to the novella Age of the Empress, the Second World War also occurred in the mirror universe, with Japan as one as its participants. One of the results appears to have been a lessening of the power of Japan's emperor, as the Kyoto Imperial Palace was turned into a tourist attraction.