Final answer:
The Adams-Onís Treaty, signed in 1819, marked the American acquisition of Florida from Spain. The United States gained control over Florida in exchange for $5 million, and this treaty also marked the boundary between the United States and New Spain.
Step-by-step explanation:
The treaty that involved American acquisition of Florida from Spain is known as the Adams-Onís Treaty. This was signed in the year 1819 where the United States assumed control over Florida in exchange for $5 million. This event came about as a culmination of incidents that took place in the past, including the American seizure of West Florida during the War of 1812, and Andrew Jackson's controversial invasion into East Florida.
Adams, instead of apologizing for the violation of Spanish territorial integrity, urged the Spanish foreign minister, Don Luis de Onís, to negotiate. The Adams-Onís treaty, also known as the Florida Purchase Treaty, not only transferred Florida to the United States but also laid down the boundary between the United States and New Spain (present-day Mexico). It was a significant agreement in American history as it opened up the way for further westward expansion.
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