"Later books, such as the Aitareya Brāhmana, which belong to the 2nd millennium BCE, speak of the expansion of the Vedic religion into regions called Uttarakuru and Uttaramadra beyond the Himalayas to the northwest. Aitareya Br. 8.14 says Uttarakuru had Vedic consecration for their kings. Ptolemy knows of these regions as Ottorokorrha and describes them lying between the Aral and the Caspian Seas and Megasthenes and Strabo are emphatic that the Uttarakuruvah [Hyperboreans] are connected with the Indians."