Background. Napoleon is worried about what would happen to his empire after he died. He was worried that it would fall apart unless he had an heir. His wife Josephine had failed to provide him with a child.
His wife Josephine had failed to provide him with a child.
So, he divorced her and created an alliance with Austria and married Marie Louise (grandniece of Marie Antoinette)
Also, the French and Russian rulers suspected each other of having competing designs on Poland. (Remember during the Enlightenment period Poland was very weak and it was ruled by the nobles but disappeared as an independent country for a while).
Because of this Napoleon had this brilliant idea to attack Russia.
Napoleon marched his army of 420,000 soldiers into Russia.
This ended Napoleon’s last chance for power, which is known as the Hundred Days.