The man responsible for negotiating a treaty for the united states to acquire florida from spain, aid in an agreement with great britain to fix the canadian-american border at the 49th parallel, and wrote a majority of the monroe doctrine is

The answer is:

John Quincy Adams.

Explanation:

eldest son of President John Adams In his prep residential years he was one of America’s greatest diplomats (formulating, among other things, what came to be called the MONROE DOCTRINE, and arranged a boundary commission that fixed the Canadian-American boundary.

Adams succeeded in getting the Spanish minister to agree to a treaty in which Spain would abandon all claims to territory east of the Mississippi River.

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