DEPARTMENT OF STATE
The President directs that, except immigrant passengers directly entering an American port by sea, henceforth no traveler shall be allowed to enter the United States from a foreign country without a passport. If a citizen, the passport must be from this Department or from some United States minister or consul abroad; and if an alien, from the competent authority of his own country, the passport to be countersigned by a diplomatic agent or consul of the United States. This regulation is intended to apply especially to persons proposing to come to the United States from the neighboring British Provinces. Its observance will be strictly enforced by all officers, civil, military, and naval in the service of the United States, and the State and municipal authorities are requested to aid in its execution. It is expected, however, that no immigrant passenger coming in manner aforesaid will be obstructed, or any other persons who may set out on their way hither before intelligence of this regulation could reasonably be expected to reach the country from which they may have started.
WILLIAM H. SEWARD.
Abraham Lincoln, Executive Order Online by Gerhard Peters and John T. Woolley, The American Presidency Project https://www.presidency.ucsb.edu/node/202824