Spain was the country which had explorers who led expeditions into the lands of the Aztecs and Incas in North and South America. These explorers were Pizarro and Cortes. Hope it help!
An alliance is someone or group you team up with.
Monroe administration had concerns over Russia.
The Monroe Doctrine was a policy of the US against European colonialism in the Americas, the doctrine was against the influence of Europe in the affairs of the newly independent Latin American states. The US was also concerned about the northwest coast of America - Alaska toward Oregon - because of Russia’s ambitions over there.
