indias empires By chantel hill 2000 BCE indus valley civilization 500 BCE buddha 500 BCE vedic period Yojurveda Samaveda Atharvaveda 470 BCE Aryabhata 380 BCE kalidasa 335 BCE mahabharata/ramayana chaturanga "four limbs/divisions" Period: 324 BCE to 297 BCE chandragupta Period: 322 BCE to 184 BCE maurya empire Period: 320 BCE to 550 BCE gupta empire Period: 270 BCE to 232 BCE ashoka