The Confederate States of America sought to ensure SLAVERY in its Confederate States of America constitution:

Constitution of the Confederate States of America
Adopted unanimously by the Congress of the Confederate States of America
March 11, 1861

Article I Section 9(1)
“The importation of negroes of the African race from any foreign country, other than the slaveholding States or Territories of the United States of America, is hereby forbidden; and Congress is required to pass such laws as shall effectually prevent the same.”

Article I Section 9(2)
“Congress shall also have power to prohibit the introduction of slaves from any State not a member of, or Territory not belonging to, this Confederacy.”

Article I Section 9(4)
“No bill of attainder, ex post facto law, or law denying or impairing the right of property in negro slaves shall be passed.”

Article IV Section 2(1)
“The citizens of each State shall be entitled to all the privileges and immunities of citizens in the several States; and shall have the right of transit and sojourn in any State of this Confederacy, with their slaves and other property; and the right of property in said slaves shall not be thereby impaired.”

Article IV Section 3(3)
“The Confederate States may acquire new territory; and Congress shall have power to legislate and provide governments for the inhabitants of all territory belonging to the Confederate States, lying without the limits of the several states; and may permit them, at such times, and in such manner as it may by law provide, to form states to be admitted into the Confederacy. In all such territory, the institution of negro slavery as it now exists in the Confederate States, shall be recognized and protected by Congress, and by the territorial government: and the inhabitants of the several Confederate States and Territories, shall have the right to take to such territory any slaves lawfully held by them in any of the states or territories of the Confederate states.”