Simplify the following text for a Grade 6 native English-speaking person.
Original: The Battle of Leipzig or Battle of the Nations , on 16 â `` 19 October 1813 , was fought by the coalition armies of Russia , Prussia , Austria and Sweden against the French army of Napoleon Bonaparte .
Simplified: The Battle of Leipzig was a battle between Napoleon I and his army and an allied force of several nations . It happened on October 16-19 on 1813 .