The Kingdom of Württemberg and the United States began relations in 1825 when both countries mutually recognized each other.
As with all of the German states that the United States had treaties with after Württemberg joined the German Empire in 1871 there were questions as to whether U.S. officials abided by treaties concluded with Württemberg or with Prussia in dealing with issues of trade, citizenship, or extradition.
First, "where a State has lost its separate existence, as in the case of Hanover and Nassau, no questions can arise."
Years after his 1891 death, Bancroft remained listed as the official diplomatic representative of the U.S. in Württemberg.
[1] This article incorporates public domain material from "A Guide to the United States' History of Recognition, Diplomatic, and Consular Relations, by Country, since 1776: Württemberg".