What does fourth millennium BC mean?

Which one is older 4000 BC or 1815 BC? What of the ancient cultures developed first? What are two sumerian innovations and how did these innovations make life easier for the sumerians? Why was lapu-lapu die? When Menelaus gives Telemachus a parting gift of a silver mixing bowl decorated with gold he is practicing which ancient ritual xenia polytheism sacrifice hubris? What is an old Italian silver coin called? How did Boudicca become the ruler of the Celts? When did alex the great empire change? Who were the pagan during the time of Augustine? Was Mark Antony and Cleopatra in all 3 triumvirate? Who is the first human individual whose name is known and whose existence can be verified? What happened during the 7th century ad? Who are Priam parents? What is a system of letters invented by the Phoenicians to make writing easier? Where did Theseus come from? What is the Aztecs kings clothing? What are Greek goddess Athena's weaknesses? What came before 1500 bc or 753 bc? What is the natural form of a skinwalker? The Olympics were not only a single famous ancient athletic game held in Greece there were three major competitons what were they?