Sixteen Most Significant Events in U.S. History between 1789 to 1975

After reviewing 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, the "Mexican-American War," against the fourth seed, the "Louisiana Purchase." The second seed in the bracket, "Marbury v Madison," is paired against the third seed, the "Monroe Doctrine." 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 of the Louisiana territory was a significant achievement for President Jefferson, who was able to expand the power of the presidency through the use of executive power. The Louisiana Purchase paved the way for future expansion and the idea of Manifest Destiny. The Mexican-American War was a pivotal event in the history of the United States. It was a conflict between the United States and Mexico that lasted from 1846 to 1848. The war was fought over territorial disputes and ended with the Treaty of Guadalupe Hidalgo, which gave the United States control of Texas, California, and other territories in the Southwest. The war had significant economic and political implications for the United States. It allowed for the expansion of slavery into new territories, which would eventually lead to the Civil War. The war also established the United States as a dominant power in North America. Marbury v Madison was a landmark case in the history of the United States. It established the principle of judicial review, which gave the Supreme Court the power to declare laws unconstitutional. The case arose out of a dispute between President John Adams and his Secretary of State, James Madison, over the appointment of judges. The Supreme Court ruled that the law giving the Court the power to hear the case was unconstitutional. The decision established the principle of judicial review and strengthened the power of the Supreme Court. The Monroe Doctrine was a foreign policy statement made by