WHAP Timeline By baileken 206 Start of the Han empire 206 End of the Qin Empire 220 End of the Han empire 221 Start of the Qin empire 224 End of the Parthian Empire 247 Parthian Empire Established 260 Date Ashoka began Supporting Buddhism 313 Constantine issued edict allowing Christanity 320 Start of the Gupta Emipre 322 Start of Mauryan Empire 323 End of the Hellenistic empire 326 Begining of the Hellenistic empire 476 End of the Roman empire 550 End of Gupta empire Mar 2, 2022 End of the Mauryan empire Mar 2, 2022 Start of the Roman empire