Coventry was a city in Great Britain.
In late 1940, Coventry suffered heavily under a Luftwaffe bombing raid during the Blitz. Richard Charlesworth's grandmother died in the raid, which deeply affected him. (PROSE: It's a Lovely Day Tomorrow [+]Martin Day, Short Trips: A Christmas Treasury (Short Trips short stories, 2004).)
Rumours circulated that Winston Churchill knew the raid was going to happen but kept quiet in order to protect a secret code. (PROSE: This Town Will Never Let Us Go [+]Lawrence Miles, Faction Paradox (Mad Norwegian Press, 2003).) Churchill admitted in his diaries to feelings of guilt regarding the city's fate. (AUDIO: Hounded [+]Alan Barnes, The Churchill Years: Volume One (The Churchill Years, Big Finish Productions, 2016).)
In March 1941, the Seventh Doctor cited Coventry to Joachim Wolff as a name on a map which would be given "new and terrible meaning" over the remainder of World War II. (PROSE: Just War [+]Lance Parkin, Virgin New Adventures (Virgin Books, 1996).)
Behind the scenes[]
In the real world, the most infamous stage of the Coventry Blitz took place in November 1940, though it also suffered further raids after this date. Just War implies it was still yet to gain its significance by March 1941, although It's a Lovely Day Tomorrow indicates the raid happened in late 1940.