Complex sentence: Kiarostami was one of the few directors who remained in Iran after the 1979 revolution, when many of his peers fled the country, and he believes that it was one of the most important decisions of his career.
Split into simpler sentences: Kiarostami was one of the few directors who remained in Iran after the 1979 revolution, when many of his peers fled the country. He believes that it was one of the most important decisions of his career.