The Louisiana Purchase opened up the United States at the time to the Midwest
Invasions of people--many of the groups came as military and fought the Romans as invading forces.
Counterclaim--they were migration patterns as they were attempting to gain access to an empire with advanced trade and education. Migrating to the Roman Empire gave a person or group with extra resources.
"<span>C. It had thin stone walls supported on the outside by flying buttresses" does not</span> apply to Gothic architecture, since the walls were often very thick.
Detente. a policy of reducing Cold War tensions that was adopted by the United States during the presidency of Richard Nixon ... What do you consider<span> the most significant reason for the collapse of </span>