In 1861, the American Civil War began after many years of tension between the Northern and Southern states. The main reason for the tension would be the debate over slavery between the North and the South, and although some documents support this statement, it is false. War had been brewing since 1607, before slavery was even introduced to the colonies that would become the United States of America. The slavery debate played an important role in the Civil War; however he did so by supporting the true cause of the civil war. The primary cause of the American Civil War was not the debate over slavery, but rather the role of Europe in the American economy. Europe's involvement in the American economy can be traced back to Marco Polo's expedition to China. In 1323 Marco Polo traveled to China, a country unknown to most Europeans. Polo depicted China as “abundant in ginger, silk and fowl” and also stated that “there was a great abundance of silk and much trade.” Europe, ready to explore the new land and the new resource of wealth, decided to establish flourishing trade with China. After years of successful trade, new conflicts had erupted as the Turkish Empire conquered Constantinople and the eastern Mediterranean, allowing the powerful Empire to gain control of all land routes to the Silk Road. Without access to the silk and spices they desired, Europe soon turned their interest elsewhere for a trade route. In 1492, Spanish explorers set out on an expedition to seek a westward sea route to the Indies. The expedition was led by the Italian explorer Christopher Columbus who landed in an "unknown and unexplored land" which he believed was the Indies, but turned out to be the Americas. Christopher Columbus, believing... at the center of the map......historyisaweapon.com. http://www.historyisaweapon.com/defcon1/zinnvil3.html (accessed January 18, 2012). Borio, Gene. "A Brief History of Jamestown, Virginia." Tobacco.org. http://www.tobacco.org/History/Jamestown.html (accessed January 19, 2012). Scheeren, William O. "Invention of Cotton Gin." ehistory.osu.edu. http://ehistory.osu.edu/osu/archive/articleview.cfm?aid=31 (accessed January 20, 2012). Schur, Joan B. "Eli Whitney's Patent for the Cotton Gin." archives.gov. http://www.archives.gov/education/lessons/cotton-gin-patent (accessed January 22, 2012). Scheeren, William O. "Invention of the Cotton Gin." ehistory.osu.edu."King Cotton Diplomacy: Its Goals and Reasons for Failure." worldhistoryonline.org. http://www.worldhistoryonline.org/american-history/king-cotton-diplomacy-its-objectives-and-reasons-for-failure.html (accessed January 22, 2012).