London is the capital city of England and the United Kingdom. It was attacked by the Chimera in October 1950 when Chimeran Burrowers dug from beneath the English Channel. The resulting siege culminated with the River Thames flooding the underground Central Command base underneath the city, killing 14,000 soldiers. This left only a small force of less than 5,000 soldiers to defend the rest of the country, as the majority of Britain's military might was lost when its Royal Navy was wiped out by freak storms in the English Channel and many of its ground troops lost in the European theatre while supporting the United European Defense. By early 1951, the Chimera ferried its entire invasion forces through massive fleet of dropships to London.
Under the Chimeran occupation, the environments of London as well as the areas surrounding the city underwent several, drastic changes: the weather dropped to below freezing point that the water in Thames River become frozen solid ice, and snowstorms and blizzards would occur frequently, and as well of the unearthing of a Chimeran hub tower in the center of the city. Sergeant Nathan Hale arrived in London just shortly after he followed the underground power conduit junction all the way from Bracknell to Chimeran tower "C-03" in London suburb of Lambeth for several miles and radioed Captain Rachel Parker that destroying the hub tower would destroy the Chimera. In the final battle of Operation Morning Star, London was retaken and liberated by joint Anglo-American military forces after the hub tower was successfully destroyed by Nathan Hale during the Battle of London on July 14th, 1951.
The destruction of the Chimeran central tower in London caused an unstable chain reaction. A reactor meltdown destroys all connected towers in the network, and eradicating all Angels in Britain. Human forces discovered that the Chimera were unable to survive with the loss of the Angels and died within minutes. After the liberation of London, all survived human soldiers are investigated the ruins of five towers as they attempt to research and reverse-engineer on Chimeran technologies, and searching in every ruins of cities and villages for uninfected survivors.