"According to well-recognized principles, both of public and private law, these agents of foreign governments having been recognized as such by the agent of the several Confederate States prior to the revocation of the powers delegated to that agent, remained so recognized after the revocation, It was and is undoubtedly within the power of this Government, as it is within the power of all governments, to decline permitting the above-mentioned agents to remain within our limits, but for obvious reasons the exercise of such a power has been deemed unwise and impolitic. The one agent who is excepted from these remarks is Ernst Raven esq., who was appointed consul for the State of Texas by his highness the Duke of SaxeCoburg and Gotha, and wire applied to this Government for an exequatur on the 30th of July, 1861."It is proper to add that a short time ago it came accidentally to the knowledge of the Department that a certain Baron de Saint Andre had assumed the functions of consul or consular agent for the French Government at the port of Charleston since the establishment of the Confederate Government and without applying for an exequatur to this Department. But just at a time this information was received intelligence was also received that Baron Saint Andre had left Charleston with his family for the United States with the probable intention of returning in the autumn. In the event of such return, proper action will be promptly taken by the Department to repress the offensive assumption of consular functions by a foreign agent without the sanction of this Government.
It should be noted that the confederate senate did not ratify a single treaty with a single foreign power.
Similarly, several Europeans governments had envoys in the CSA during the War to look after their economic interests. Some of them, at least, were foreign nationals already living there. The CSA failed to get even one country to formally recognize its existence. The reason is simple; by doing so, the recognizing country would have necessarily endangered or lost its relationship with the legitimate government of the country.
From Bouvier's Law Dictionary,, Rev. 6th ed., (1856):EXEQUATUR, internat. law. A declaration made by the executive of a government near to which a consul has been nominated and appointed, after such nomination and appointment has been notified, addressed to the people, in which is recited [written] the appointment of the foreign state, and that the executive having approved of the consul as such, commands all the citizens to receive, countenance, and, as there may be occasion, favorably assist the consul in the exercise of his place, giving and allowing him all the privileges, immunities, and advantages, thereto belonging.