Which founding father went to London in the 1780s in order to try and resolve problems leftover by the American Revolution

John Adams.

Explanation:

Before being President, John Adams was a prominent American diplomat in Europe.

In 1778, Adams was sent to Paris to obtain support for the United States from the French. The following year, he returned to the United States to formulate his own constitution for the state of Massachusetts.  

In November 1779, Adams returned to Europe on a diplomatic mission and, together with John Jay and Benjamin Franklin, obtained the Treaty of Paris in 1783, which ended hostilities between the British and American settlements.

Adams also worked simultaneously in the Netherlands, where he negotiated a $ 2 million loan to the United States. The Dutch provinces recognized U.S. independence in April 1782, and Adams was received as the U.S. ambassador.

After the end of hostilities, Adams was appointed the first British ambassador to the United Kingdom in 1785. He held this position until 1788 and then returned to the United States.

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