As the right to hold slaves was guaranteed to those who owned them prior to the passage of the Ordinance of 1787, it was to be expected that those attached to that institution would not indifferently see it pass away.

Various petitions, therefore, were sent to the territorial legislature and to Congress praying that the sixth article of the Ordinance of 1787 be abrogated.[24] No formal action to this effect was taken, but the practice of slavery was continued even at the winking of the government.

Some slaves came from the Canadians who, in accordance with the slave trade laws of the British Empire, were supplied with bondsmen.

It was the Canadians themselves who provided by act of parliament in 1793 for prohibiting the importation of slaves and for gradual emancipation.

When it seemed later that the cause of freedom would eventually triumph the proslavery element undertook to perpetuate slavery through a system of indentured servant labor.
In the formation of the States of Indiana and Illinois the question as to what should be done to harmonize with the new constitution the system of indenture to which the territorial legislatures had been committed, caused heated debate and at times almost conflict.