The Monroe doctrine was the reaction and effect of the European powers plan to help Spain create or retake colonies in America. the doctrine, enacted in 1823,pointed out that the USA would intervene to protect the peace and freedom of independent states in the region of America.
Generally speaking, a polis of ancient Greece was a "City State," in which there was a great deal of autonomy and self-governance, which was a goal of many Greek philosophers of the day.
