The Moroccan landscape, titled “Tower of the Koutoubia Mosque”, was completed by Churchill at the January 1943 Casablanca Conference, making it the only painting of Churchill’s done during the Second World War.
The image shows a 12th-century mosque in Marrakech at sunset, with the Atlas Mountains in the background.
Including commission, the painting sold for £8.285m at auction at Christie’s on Monday (1 March).
It was expected to make between £1.5 and £2.5m at auction and smashed records for Churchill’s previously most expensive painting, which sold for £1.8m.
Two more of Churchill’s paintings also went under the hammer on the same day, with the three works collectively fetching £9.43m.
The painting was gifted to US president Franklin D Roosevelt on a trip to Marrakech after the conference by Churchill.
It was later sold by Roosevelt’s son, with Jolie and her former partner Brad Pitt becoming one of its later owners in 2011.
The painting was sold by the Jolie Family Collection. The buyer wasn’t immediately identified.