Historical reports argue that the idea behind War of the Worlds was inspired by a novel that was previously released in 1871 by George Chesney called The Battle of Dorking. An "invasion novel" of near apocalyptic proportions, Dorking relates the story of how an invasion force from Germany landed in a town in England, and ended up in one last deadly battle in Dorking, Surrey. The result of the two forces battling it out was reckless havoc, the end of the British Empire, and the end of the English rule. Considering the growing economic and industrial power that England represented at the time, any literature having to do with exterminating the British power must have been impacting enough. But Dorking was powerful; so powerful that it actually made the British Army mobilize, even with no direct threat, to always be protected from the Germans. In not so many words, The Battle of Dorking was so seared in the British psyche that it must likely have affected H.G. Wells as well.
To add more evidence to this argument, it is notable that the novel mentions a war tool called a "wonder weapon" to finish the job against England. This curious bit, an enigmatic concept that was still more ahead of its time, places Dorking under the genre of science fiction which, as is well-known, would be H.G. Wells' forte.
According to the book The Biological Universe: the Twentieth Century Extraterrestrial Life Debate , H.G. Wells and his brother Frank came up with the idea of the book in a dialogue that is recorded as follows:
"Suppose some beings from another planet were to drop out of the sky suddenly," said Frank, "and begin laying about them here!"
This was 1898, however, England was about to rule the world, and Dorking had already made its mark in the world. What could happen next? Enter War of the Worlds.
In a time where space exploration was many years away, the only thing that could have matched the concept of Dorking would have been a bigger, more outrageous, and more impossible war. If you read Dorking you realize that the plot, the action, and the situations are basically the same as the one Wells writes about in Worlds with the exception that Worlds has extraterrestrials from Mars as the alien invaders. Think of War of the Worlds as a rather futuristic version of The Battle of Dorking.
Therefore, history shows us that War of the Worlds is a simple, well-stated title for a novel where another big war was about to take place. What type of war? One that would surpass anybody's imagination.