Wyndham frequently acknowledged the influence of H. G. Wells' The War of the Worlds (1897) on The Day of the Triffids[7][8]— Wells's working title had been The Day of the Tripods.
The triffids are related, in some editions of the novel, to brief mention of the theories of the Soviet agronomist Trofim Lysenko, a proponent of Lamarckism who eventually was thoroughly debunked. "In the days when information was still exchanged Russia had reported some successes. Later, however, a cleavage of methods and views had caused biology there, under a man called Lysenko, to take a different course" (Chapter 2). Lysenkoism at the time of the novel's creation was still being defended by some prominent international Stalinists."[9]
During the Blitz, Wyndham was a fire watcher and later member of the Home Guard. He witnessed the destruction of London from the rooftops of Bloomsbury. He described many scenes and incidents, including the uncanny silence of London on a Sunday morning after a heavy bombardment, in letters to his long-term partner Grace Wilson. These found their way into The Day of the Triffids.[10]
