When Does "The Imitation Game" (2014) Take Place?
"The Imitation Game" is a historical fiction film written by Graham Moore that released November 28th, 2014. So when is "The Imitation Game" set?
It takes place in the years:
We know this because a place and time setting title card marking "1939" appears early in the film over footage of a newsboy barking to sell copies of a newspaper announcing the September 1939 evacuation of British children at the start of World War II. So it must be September of 1939 AD.

1939 AD - 1945 AD
We know this because a place and time setting title card marking "1939" appears early in the film over footage of a newsboy barking to sell copies of a newspaper announcing the September 1939 evacuation of British children at the start of World War II. So it must be September of 1939 AD.
The main action of the story resolves when World War II ends in 1945 AD.
Additionally, the film opens with a place and time setting title card before a single frame of footage that reads "1951". This labels the entire 1951 AD framing narrative, shown at the beginning and end but also threaded through the film, of Alan Turing (1912-1954) being investigated after the war. Though, at least one of the scenes at the end of the movie depicts something that happened in the real world on June 7th, 1954 AD. So at least this part could be placed in June of 1954 AD.
Additionally, the film opens with a place and time setting title card before a single frame of footage that reads "1951". This labels the entire 1951 AD framing narrative, shown at the beginning and end but also threaded through the film, of Alan Turing (1912-1954) being investigated after the war. Though, at least one of the scenes at the end of the movie depicts something that happened in the real world on June 7th, 1954 AD. So at least this part could be placed in June of 1954 AD.
Additionally, there are five flashbacks to Turing's time as a student at Sherborne School in 1928 AD. The first of these is clearly labeled by a place and time setting title card that says "1928". Though one of these scenes includes a tragic turn which happened in the real world in February of 1930 AD.