This person was the first to use the phrase "Iron Curtain" in relation to the USSR.
Winston Churchill
Ethel Snowden
Joseph Goebbels
Joseph Stalin
Ethel Snowden used the phrase "iron curtain" in her 1920 book, Through Bolshevik Russia, describing the border of the Soviet Union as an impenetrable barrier: "we were behind the ’iron curtain’ at last."