A.) the end of the soviet blockade
In 622 Muhammad fled Mecca after hearing of a plot to assaninate him.
During the century that followed Pax Romana, Rome had many leaders because men were fighting for power of the empire. This time period is know as "The Crisis of the Third Century ". It was during this time that the Roman Empire almost collapsed entirely because of several combined pressures including civil war, invasions, plague and economic depression.
