Why did slavery become a widespread institution in eighteenth-century colonial North America?

Regarding slavery in colonial North America: There was a market for tobacco and(in South Carolina) rice, and there was lots of cheap land on which to grow them, but no dependable source oflabor to work the land and produce the marketable goods.Pohnpei397's first reason given is correct.  His second reason needs a bit of correction, that is to say, some authorities do not entirely agree with him:  Actually plantation owners got more work out of indentured servants for the time that they owned them, than out of permanently enslaved servants, because they drove the indentureds harder knowing that they would not have them for life but for a few years only.  See Morgan, "American Slavery, American Freedom" on this.  The problem with indentureds was: not enough of them and they often ran away and were hard to detect and recover once they got beyond the community in which they were known to be indentured.

Another answer states that slaves could be completely controled by their masters: No more is that true of slaves than of any other human employees except as to physical location; slaves slowed down their work, attempted to deceive their masters, broke their work tools, hid their work tools, stole food from storage buildings, ran away to the swamps for a two-week vacation, and did all of the other things that modern employees do.  Also, indentureds could be sold and their period of indenture could be extended rather (not completely) arbitrarily; if an indentured ran away and was recapured, the period of indenture was extended; also for various forms of resistance or disrespect to the master, the period of indenture could be extended.

As for one answer, that breeding houses were kept where strong male slaves were used as studs to breed more slaves, I don't know that this is false, but in a graduate course "The Old South", an undergraduate course "The South in History and Literature," and in several other books on the Old South that I have read, I have never even seen such a thing suggested.  It is true that many owners did not encourage marriage by slaves; those owners' slaves mated randomly.  Other owners did encourage marriage of slaves, but maintained the same right they had over their own daughters, of approving the slave's selection of a marriage partner before the marriage could take place.

I have strayed off of your topic.