Complex sentence: Arovsev would run afoul of the secret police in 1937 during the Terror of 1937-38 and was replaced by Viktor Fedorovich Smirnov, who remained as head of VOKS until 1940.
Split into simpler sentences: Arovsev would run afoul of the secret police in 1937 during the Terror of 1937-38. He was replaced by Viktor Fedorovich Smirnov, who remained as head of VOKS until 1940.