Texas Declaration Of Secession:
“She was received as a commonwealth holding, maintaining and protecting the institution known as negro slavery – the servitude of the African to the white race within her limits – a relation that had existed from the first settlement of her wilderness by the white race, and which her people intended should exist in all future time.

[…]But what has been the course of the government of the United States, and of the people and authorities of the non-slave-holding States, since our connection with them?
The controlling majority of the Federal Government, under various pretenses and disguises, has so administered the same as to exclude the citizens of the Southern States, unless under odious and unconstitutional restrictions, from all the immense territory owned in common by all the States on the Pacific Ocean, for the avowed purpose of acquiring sufficient power in the common government to use it as a means of destroying the institutions of Texas and her sister slave-holding States.

[…] We hold as undeniable truths that the governments of the various States, and of the confederacy itself, were established exclusively by the white race, for themselves and their posterity; that the African race had no agency in their establishment; that they were rightfully held and regarded as an inferior and dependent race, and in that condition only could their existence in this country be rendered beneficial or tolerable.”

Virginia Ordinance Of Secession:
“[…]the Federal Government having perverted said powers not only to the injury of the people of Virginia, but to the oppression of the Southern slave-holding States”

Alabama Ordinance Of Secession:
“Whereas, the election of Abraham Lincoln and Hannibal Hamlin to the offices of president and vice-president of the United States of America, by a sectional party, avowedly hostile to the domestic institutions and to the peace and security of the people of the State of Alabama, preceded by many and dangerous infractions of the constitution of the United States by many of the States and people of the Northern section, is a political wrong of so insulting and menacing a character as to justify the people of the State of Alabama in the adoption of prompt and decided measures for their future peace and security,

[…]And as it is the desire and purpose of the people of Alabama to meet the slaveholding States of the South, who may approve such purpose, in order to frame a provisional as well as permanent Government”

South Carolina Declaration Of Secession:
“But an increasing hostility on the part of the non-slaveholding States to the institution of slavery, has led to a disregard of their obligations, and the laws of the General Government have ceased to effect the objects of the Constitution. […] In many of these States the fugitive is discharged from service or labor claimed […] and the States of Ohio and Iowa have refused to surrender to justice fugitives charged with murder, and with inciting servile insurrection in the State of Virginia. Thus the constituted compact has been deliberately broken and disregarded by the non-slaveholding States, and the consequence follows that South Carolina is released from her obligation.”

Georgia Declaration Of Secession:
“For the last ten years we have had numerous and serious causes of complaint against our non-slaveholding confederate States with reference to the subject of African slavery.”

Mississippi Declaration Of Secession:
“Our position is thoroughly identified with the institution of slavery – the greatest material interest of the world. Its labor supplies the product, which constitutes by far the largest and most important portions of commerce of the earth. These products are peculiar to the climate verging on the tropical regions, and by an imperious law of nature, none but the black race can bear exposure to the tropical sun. These products have become necessities of the world, and a blow at slavery is a blow at commerce and civilization.

[…]It advocates negro equality, socially and politically, and promotes insurrection and incendiarism in our midst. It has enlisted its press, its pulpit and its schools against us, until the whole popular mind of the North is excited and inflamed with prejudice.

[…]It has given indubitable evidence of its design to ruin our agriculture, to prostrate our industrial pursuits and to destroy our social system.
It knows no relenting or hesitation in its purposes; it stops not in its march of aggression, and leaves us no room to hope for cessation or for pause.
It has recently obtained control of the Government, by the prosecution of its unhallowed schemes, and destroyed the last expectation of living together in friendship and brotherhood.”

[…]all of the listed secondary reasons were unambiguously knock-on effects of measures enacted by Free States to punish Slave States