What event led president monroe to issue the monroe doctrine?

The Monroe Doctrine was named after the President that delivered the message to Congress in 1823,but the Doctrine was the brain child of Secretary of State John Quincy Adams.Basically,the Doctrine warned that the United States was no longer to be considered an area open to European influence or colonization.The Us promised not to interfere in the affairs of Europe and Europe would respect that the fact that the  Western Hemisphere was closed to colonization and influence by any other power than the Us.