[1] The term implies a positive judgement defining a "normative period" in Islamic history, but western scholars generally extend the period much later than Muslim scholars would allow.
[2] The Muslim conception of a normative period corresponds mainly to that of the Companions of the Prophet and the Rightly Guided Caliphs, roughly the seventh century.
The term may be given a primarily religious sense, meaning "the era when the classics of Islamic law and spirituality were written", extending down to about 1400.
Although "reality had failed to conform for rather more than four centuries" to the ideal of the caliphate, the collapse of 1258 represents a fundamental psychological break in Islamic history.
[2] In a more restricted sense, Islamic "classical civilization" corresponds to the "high caliphal" period of the Umayyads and Abbasids from about 692 to 945, when "Islamicate society formed a single vast state".