It is uncertain whether historians of Cambodia devote as much space to the country's brief revolutionary period as to the much longer, more complex, and more mysterious Angkorean era. The Communist regime that controlled Cambodia between April 17, 1975, and January 7, 1979, was known as Democratic Kampuchea (DK). The DK period can be divided into some phases. One is lasted from the capture of Phnom Penh until the beginning of 1976 when DK formally came into existence, a constitution was proclaimed. DK's another phase lasted until the end of September 1976 and marked the apogee of the regime. The next phase of the DK era, between the political crisis of September 1976 and a speech by Pol Pot twelve months later in which he announced the existence of the Cambodia's Communist Party, was marked by waves of purges.