Whats the authors main purpose of the text

Whenever someone writes something, they do it for a reason. This is called the author's purpose. There are three types of author's purpose and you probably already know them, but you just don't really think about them.

on november 6 and 7, 1917 (or october 24 and 25 on the julian calendar, which is why the event is often referred to as the october revolution), leftist revolutionaries led by bolshevik party leader vladimir lenin launched a nearly bloodless coup d'état against the duma's provisional government.