Texan Annexation. Mexico had warned it would regard annexation as an act of war. When it took place, Mexico did not declare war, but broke diplomatic relations.
The Boundary Dispute. Regardless of its status (was it an American state or a rebellious Mexican province?), the United States maintained that the southern border of Texas was formed by the Rio Grande, but Mexico argued that the traditional boundary was at the Nueces River farther north.
The California Question. President Polk clearly wanted to expand the country to the Pacific Ocean by taking control of California and lands in the Southwest – a prime example of the prevailing Manifest Destiny mentality.
Monetary Claims against Mexico. The United States had extracted a promise from the Mexican government to pay $3 million to cover the claims of American citizens who had lost property during turmoil and revolution. Mexico defaulted on those payments and the American creditors pressed their government for action.
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Causes of The Revolutionary War ... Of The War The following events represent the major events along the way to war. While it would be hard to point to any one event that singularly led to the Revolution, there is no doubt that the American view that they were entitled to the ... http://www.historycentral.com/Revolt/causes.html
Causes of the Civil War During the entire life of the Republic the respective rights and powers of the States and general government had furnished a question for endless controversy. In process of time this controversy assumed a somewhat sectional phase. The ... http://www.civilwarhome.com/gordoncauses.htm
