What are the chances that the entire world chronology is incorrect? All history is dated according to 1 ad birth of jesus. When sumer and egyptian civlizations were found, people thought the bible was historical and dated civilizations after the supposed flood event of 4000 bc. Alexander is said to be 300 years after jesus after twisting and modifying greek calender a whole bunch of times to arrive at modern calender, so if the sheet anchor of 1 ad is wrong, the date of alexander is wrong and so the date of the entire greek civilization is wrong. As the chronology is built, the inaccuracies would build upon each other.