Analysis of information sources in references of the Wikipedia article "خراسان" in Persian language version.
In pre-Islamic and early Islamic times, the term “Khurassan” frequently had a much wider denotation, covering also parts of what are now Soviet Central Asia and Afghanistan; early Islamic usage often regarded everywhere east of western Persia, sc. Djibal or what was subsequently termed 'Irak 'Adjami, as being included in a vast and ill-defined region of Khurasan, which might even extend to the Indus Valley and Sind.
Khorāsān was first named, however, by the Sāsānians (beginning in the 3rd century BC), who organized their empire into four quarters (named from the cardinal points), Khorāsān being literally the “Land of the Sun. ”
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