March 10, 1868
To the Senate of the United States:
I transmit, for the consideration of the Senate with a view to ratification, a treaty between the United States and His Majesty the King of Prussia, in the name of the North German Confederation, for the purpose of regulating the citizenship of those persons who emigrate from the Confederation to this country and from the United States to the North German Confederation.
ANDREW JOHNSON.
Andrew Johnson, Special Message Online by Gerhard Peters and John T. Woolley, The American Presidency Project https://www.presidency.ucsb.edu/node/202394