Simplify the following text for a Grade 13 native English-speaking person.
Original: The Night of the Long Knives ( German : ) or `` Operation Hummingbird ( Kolibri ) '' , or , more commonly used in Germany `` RÃ hm-Putsch '' was a purge that took place in Nazi Germany between June 30 and July 2 , 1934 , when the Nazi regime carried out a series of political executions .
Simplified: The Night of the Long Knives ( German : ) or `` Operation Hummingbird '' , was a purge that took place in Nazi Germany between June 30 and July 2 1934 , when the Nazi regime executed at least 90 people for political reasons .