WHAP timeline 10/19 By grahamer 206 Start of Han Empire B.C.E. 206 End of Qin Empire B.C.E. 221 Start of Qin Empire B.C.E. 224 End of Parthian Empire B.C.E. 247 Start of Parthian Empire B.C.E. 312 Constantine allowed Christianity C.E. 320 Start of Gupta Empire C.E. 323 Start of Alexander's Hellenistic Period B.C.E. 324 Start of Mauryan Empire B.C.E. 476 End of Roman Empire C.E. 476 End of Roman Empire C.E. 500 Ashoka began promoting Buddhism B.C.E. 550 End of Gupta Empire C.E. Oct 19, 1927 Start of Roman Empire B.C.E. Oct 19, 1930 End of Alexander's Hellenistic Empire B.C.E. Mar 2, 2022 End of Mauryan Empire B.C.E.