In 1846, the United States and Mexico went to war, after 25 years of escalating tension.
One cause of that tension was the claims filed by U.S. citizens against Mexico. Since the early 19th century, U.S. citizens had been conducting business in Mexico, and with Mexicans. When they felt wronged, they filed claims.
Their claims--for which they often submitted extensive documentation--provide us a glimpse into the experiences of U.S. citizens in Mexico in the years leading up to when the two countries went to war in 1846.
This site is a database of those claims. It goes beyond simply the financial data, though. It provides information about the claimants and the circumstances of the claims. It attempts to track the activities of U.S. citizens in Mexico through these claims.
Currently this database contains 65 claims.