On the basis of "property" rights.
You have to understand the war had VERY LITTLE to do with slavery.
Slavery warps everyone
Poor southern whites fought to defend many things. These people fought to keep their land, their rights, and often their workers.
The Southern whites were FOR slavery and the Northern whites were AGAINST slavery. So using the word patriots isn't correct because Americans are all considered patriots.
Some whites in the South justified slavery on the basis of religion (using biblical passages such as the so-called "curse of Ham" or the passage in Philemon where Paul seemingly supports slavery) to say "God has put whites in power over blacks; therefore, slavery is OK." Others justified slavery for economic reasons: "It's cheap to use slaves' free labor; the economy will collapse if we have to pay them." Others used fallacious scientific reasons (such as "whites have bigger skulls than blacks, so slavery is OK because whites must be smarter"). Others used cultural reasons ("slavery is part of the Southern way of life"). Others were just racist ("blacks are degraded animals and inferior to us; we can do whatever we want to them"). Many used a combination of several of these reasons.
Slavery began in Virginia and Maryland on tobacco farms. Slavery became more and more important as farms became bigger. That divided the Southern whites into two classes.
Southern farm owners needed the cheap labor to raise crops. Northern whites did not think it was good.
There was great variation in the reasons for fighting. As generalisations though, some of the prime reasons that poor whites fought were to defned their homeland and to maintain the Southern society that they were familiar with.
The Impending Crisis of the South
While it is never a good idea to generalize, studies have shown that large majorities of southern whites accepted slavery. Some even felt it was the right thing, because they believed that black people (then called "negroes") were inferior and meant to be slaves. But other southern whites were somewhat more ambivalent about it; we know this because even though they kept slaves, they later arranged to set them free. It is also true that the way slaves were treated varied: some owners were harsh and brutal, while others were somewhat more humane. Still, there was little public discussion about whether keeping slaves was ethical, and most southern whites seemed to support slavery as a necessity for running a plantation. Based on newspaper and magazine articles of that time, we can conclude that a large majority of southern whites were in favor of slavery, or if they had their doubts, they were not vocal about them. But it should be noted that there were a few southerners who were opposed to slavery and who did their part to try to end it. Unfortunately, their views were not the dominant ones, so slavery persisted.
Slavery stayed in the sourthern states because the whites were too lazy to do all the work themselves so they asked the goverment to ley slavery continue so that's what happened
The Impending Crisis of the South by Hinton R. Helper
because the whites did not be long in the same school and state
Because slave-labour was the mainstay of the Southern economy, in which they gained their livelihood. In the war, the poor white trash were not actually fighting for slavery, any more than most Union soldiers were fighting against it. The average Confederate soldier was wanting to defend his homeland, and was also the sort of person who would be looking forward to a darned good fight.
we whites had to do stuff on our own
Many northern whites object to slavery because it caused issues when new land was annexed because they wanted a balance.
So that the poor whites could have slaves get thangs for them
it seperated the races treating non whites as less than whites
For the blacks because they had no rights...For the whites they were fighting each other over the issue
Poll taxes and literacy tests
6,100,000 Southern people owned no slaves.