was he an ambassador to any one?
Yes - Dutch Republic.
John Adams
On April 19, the States General in The Hague formally recognized American independence and acknowledged Adams as ambassador. 
states that entered the union during presidential terms North Carolina, Rhode Island, Vermont, Kentucky, Tennessee when was george elected as president? April 30, 1789 was anyone the president before him? No, he was the first president of the United States where did he reside as a president? UNANSWERABLE who was elected as vice president then? John Adams
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John Adams [SEP] Ambassador to the Dutch Republic
Several provinces began recognizing American independence. On April 19, the States General in The Hague formally recognized American independence and acknowledged Adams as ambassador. On June 11, with the aid of the Dutch "Patriotten" leader Joan van der Capellen tot den Pol, Adams negotiated a loan of five million guilders. In October, he negotiated with the Dutch a treaty of amity and commerce. The house that Adams bought during this stay in the Netherlands became the first American embassy on foreign soil.