Sixteen Most Significant Events in US History between 1789 to 1975

After a review of United States\' history from 1789 to 1975, I have
identified what I believe are the sixteen most significant events of that
time period. The attached sheet identifies the events and places them in
brackets by time period. The following discussion provides my reasoning
for selecting each of the events and my opinion as to their relative
importance in contrast to each other. Finally, I have concluded that of
the sixteen events, the Civil War had the most significant impact on the
history of the time period in which it occurred and remains the most
significant event in American history.

The discussion begins with bracket I covering the period from
1789-1850, and pairs the number one seed in the bracket "Mexican-American
War" against the fourth seed "Louisiana Purchase". The second seed in the
bracket "Marbury v Madison" is paired against the third seed "Monroe

The purchase of Louisiana from France in 1803 was the most popular and
momentous event of the Jefferson presidency. It had several significant
economic and political implications on this period in history. From an
economic perspective it doubled the size of the United States at a price of
only fifteen million dollars. It allowed settlement beyond the Mississippi
River in a territory that was rich in minerals and natural resources. It
eliminated the United States\' long struggle for control of the Mississippi
River and its outlet to the sea, and as Jefferson stated, it freed America
from European influence at its borders. In addition to these economic
implications, the purchase also had historic political implications. The
acquisition took place at a time when the government was still exploring
the powers that the Constitution had granted it. Jefferson, himself,
carefully deliberated whether the Constitution granted him the right to
acquire territory for the purpose of expandi the Union. He reflected on
the possible need for an amendment to the Constitution to justify the
action. Finally, under intense pressure, he allowed the purchase and set
an important precedent. His action established the power of the president
to expand the borders of the United States under the existing powers of the

Despite the economic and political implications of the Louisiana
Purchase, the Mexican-American War (1846-1848) had more significant
historical implications on this time period. While disagreements between
the two countries had been accumulating for two decades, the war was
primarily the result of American feelings of "manifest destiny" to expand
their borders. The treaty of Guadalupe Hidalgo, which ended the war,
granted the United States the regions of California, Nevada and Utah, and
parts of Arizona, New Mexico, Colorado, and Wyoming. However, the
significant result of the war on United States\' history would be the
controversy over whether the territories acquired should be slave or free.
The country, at this time, was divided between proslave sentiment in the
South and antislave sentiment in the North. Various attempts at compromise
to settle the controversy, such as "The Compromise of 1850" and the "Kansas
Nebraska Act" failed. Finally, when the issue could not be resol
peacefully, the country was drawn into a civil war. It is evident that the
outcome of the Mexican-American War became one of the most influential,
indirect causes of the Civil War.

Both the Louisiana Purchase and the Mexican-American War expanded
United States borders and had beneficial economic impacts. However, the
implications of expansion brought about by the Mexican-American War were
more significant. While the Louisiana Purchase helped define the
constitutional powers of the president, the Mexican-American War further
exacerbated the slave issue which ultimately resulted in civil war.

The Monroe Doctrine was the most important assertion to date of United
States\' foreign policy in history. The doctrine was delivered by President
James Monroe as part of his annual message to Congress in 1823. This
statement of position would dictate the policy of the United States in
international affairs for years to come. The doctrine was in reaction to
continual interference of European nations in the affairs of Latin America.
It provided a framework for how the United States would deal with foreign
intervention in the western hemisphere. It stated that Europe was to remain
out of the affairs of countries in the western hemisphere and any attempt
to intervene would be viewed as a threat to the United States. In return,
the United States agreed to stay out of European affairs.

Marbury v Madison is arguably one of the most important decisions by
the Supreme Court in United States\' history. The case, which was presided
over in 1803 by Chief Justice John Marshall, concerned President Adams\'s
appointment of