|name=Seven Hour War
|image=FileBME newspaper clips.jpg|300px
|begin=After the Black Mesa Incident
|end=Seven hours after it began
|result=Decisive Combine victory Total capitulation of all Earth's governments Combine occupation of Earth
|commanders2=Unknown (presumably Advisors and higher ranked beings of Combine)
|casual1=Massive human death toll, capitulation
|casual2=Unknown, presumably light to moderate
The '''Seven Hour War''' was a brief but decisive confrontation between the Combine and the governments of the Earth, ultimately leading to a large human death toll and the Combine occupation of the entire planet.
The war itself is never discussed directly in Half-Life 2, but it is mentioned briefly by Eli Vance in Black Mesa East — looking at a small cork-board featuring several annotated newspaper cutouts and images causes him to reminisce over the events during the war. In ''Half-Life 2 Episode Two|Episode Two'', Eli states that if the super-portal matures, "''it'll be the Seven Hour War all over again... except this time we won't last seven minutes!''".
After the war had ended, the Resistance was formed to combat the new Combine leadership.
The Portal Storms raged across the Earth, (and still do according to Marc Laidlaw) spreading Xen life forms across Earth causing the people to move into cities for protection. These portal storms attracted an alien empire known as the Combine that defeated all of Earth's armed forces in only seven hours. It was after this that Wallace Breen|Dr. Wallace Breen negotiated a surrender on behalf of the United Nations, "saving" the survivors at the cost of their freedom. Breen was appointed ruler of Earth, but remains under the control of the Combine. The official surrender appears to have taken place in New York City, in the United Nations building.
At the beginning of ''Half-Life 2'', the G-Man makes a brief reference to the war, telling Gordon Freeman that "all the effort in the world would have gone to waste." This is generally understood to be a direct reference to the war, the establishment of Dr. Breen's terror state, and the reasons for Freeman's stasis. Despite Freeman's superhuman triumph at Black Mesa, there was nothing that he or the entire human race could have done to save Earth from the superior forces of the Combine empire.
''Half-Life 2'' begins an undisclosed number of years after this war, after the rule of the Combine has been firmly established. There is, however, some evidence from the ''Half-Life 2 Episode One'' official website indicating that ''Half-Life 2'' takes place nearly two decades after the Black Mesa incident.http//ep1.half-life2.com/story.php Summary of ''Half-Life'' and ''Half-Life 2'' in the official ''Half-Life 2 Episode One'' website. Retrieved on August 26, 2006. Such a time frame is logically consistent with the aging of the series' characters between ''Half-Life'' and ''Half-Life 2''. It also explains why there are no children in the game, the Combine having set up a reproductive suppression field a short time after the war preventing any further reproduction for approximately 20 years until the events of ''Episode One'', with the suppression field being disabled after the damage the Citadel had taken.
* The name may be a reference to the WikipediaSeven Years' War|Seven Years' War of 1756 to 1763, a war between France and Great Britain, or alternatively to the WikipediaAustro-Prussian War|Seven Weeks' War between Austria and Prussia in 1866.
* It could be a reference to Arab-Israeli conflicts, namely Six-Day War and Seven-Day War. They may have extrapolated a derivative function from all wars mentioned here (Year->week->Day->Hour).