The Fallout world exists in an alternate timeline that diverged from the real world timeline after World War II. From this split until the Great War in 2077, a stylized representation of 1950s American culture (with more advanced technology) dominated the Fallout world. The science fiction anthology world of tomorrow released during the Golden age of Science fiction in the 1950s, heavily influenced this representation.

Overview

Although the Fallout universe and the real world share a common timeline until about 1945, the defining moment of the Fallout universe was the Great War of 2077. On October 23, 2077, the United States, China, and other nuclear-armed countries commenced a brief but rapid exchange of nuclear strikes. Although the conflict lasted only two hours, the destruction it brought was staggering and complete: more energy was released in the early moments of the war than in all previous global conflicts combined.

The world that remained was harsh and unforgiving. 90 years after the Great War, humanity survived but struggled to do so. Above ground, small bands fought over the crumbling remains of once great cities while mutants prowled the irradiated wastes. Underground, a fortunate few enjoyed the relative safety and comfort of the Vaults. Some fought to keep the world out, others to connect with and re-populate it. Wherever humanity survived it was under constant threat by psychotic mutants, rogue machines, vicious raiders, and all manner of hostile mutant cretures.

For most of human history, the Fallout universe and the real world shared a common timeline. However, in 1945, significant political and technological differences in the Fallout timeline set it on a different course. In 1947, the transistor was not discovered and miniaturization of electronics was neglected. Some time before 1969, in an attempt to mitigate the influence of Communism, the United States adopts a system of 13 Commonwealths. In 1970, China fails to adopt any free market reforms and ends up retaining a political and economic structure similar to what it had under Communist Party Chairman Mao Zedong. In 1991, the USSR did not collapse.

No major international conflicts would take place until the middle of the twenty-first century. In 2052, the oil rich Middle East nations raised oil prices causing the economic collapse of many smaller countries. The European Commonwealth (analogous to the real world European Union), similarly dependent on oil imports from the Middle East, begins the Resource Wars by responding with military force. The United Nations, weakened by its inability to prevent the conflict, attempts to intervene. Many of its member nations respond by withdrawing and the UN disbands that year.

The United States, supplied with oil from Texas and Mexico, escaped any direct impact from the Resource Wars. However, the U.S. would soon have significant problems of its own. In 2052, the Texas oil fields run dry, making the country severely vulnerable to energy shortages. In 2053, the New Plague begins to ravage the U.S. population, causing an estimated 200,000 deaths and prompting the government to close the country's international borders. Nuclear fears grip the country when, in the same year, Tel Aviv is destroyed by a terrorist nuclear weapon and, in the following year, warring nations exchange nuclear weapon strikes in the Middle East. In response, the Americans begin Project Safehouse: a series of underground Vaults designed to survive nuclear war or an epidemic.

In 2059, oil resources grow increasingly scarce. To secure the Alaskan oil fields the United States ramps up its military presence in that state, creating the Anchorage Front Line. Relations with Canada grow increasingly strained as the Americans press to have their military units stationed on Canadian soil to protect the Alaskan pipeline.

In 2060, the Middle East oil fields run dry. This not only ends the Resource Wars in Europe, but the European Commonwealth as well. Without a common enemy, the European nations begin fighting among each other for the remaining resources. Fossil fuels become too expensive to use in automobiles and alternatives begin to appear in the market. Advances in nuclear technology pave the way for nuclear fusion to replace traditional fossil fuel-based combustion engines in automobiles and other vehicles.

Great War

In 2066, the Resource Wars shift to the other side of the globe. China, their oil reserves exhausted and their economy near collapse, invades Alaska. America strong-arms Canada into allowing troops and planes to move across Canadian territory on their way to the Alaskan theater. Relations between the neighboring countries would continue to worsen as the Americans help themselves to Canadian resources, ignoring Canadian protests. Many Americans begin referring to Canada as "Little America." Their comments do not help the situation.

In 2072, the Sino-American War grinds on. While American power armor proves effective in localized conflicts, it fails to completely dislodge Chinese forces. The U.S. continues to demand more resources from Canada. When an attempt is made to sabotage the oil pipeline, the Americans (officially) begin to annex Canada. In 2076, the annexation is complete. Also that year Americans deploy the T-51b power armor to the Chinese mainland. The suits are highly effective and American troops cut a swath through Chinese territory.

In early 2077, the Americans reclaim Alaska but no armistice is signed.  The American public, having been exposed to too many false alarms, largely ignore the warning sirens when the bombs begin to fall. Many Vaults are underpopulated as their doors are shut.

In the early hours of October 23, 2077, the world--as everyone knew it--ended. Missiles and bombs rained from the sky, engulfing the world in flames in an event that would become known as the Great War. Cities and nations fell, and humanity descended into a nuclear Dark Age. Many believed it was the end of human civilization, but instead it was simply the beginning of a new and bloody chapter.

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