While the details I've worked out may be found lacking by serious historians, the blockade of Southern shipping by the North, the South's embargo of its own cotton, and the destruction of the Southern economy by Sherman mean we should not take for granted that all of today's American blacks are actually the descendants of slaves. Many if not most slaves may have starved to death during the war. Food may have been shorter in the South than the history books tell. Besides that, many slaves were probably sold during the war so the South could buy weapons. The blacks we have today may be in part descended from replacements secretly brought in with the government's help so the South could continue to be the source of the nation's cash exports. The slaves could have been replaced in postwar generations by large Southern landowners who needed a workforce, didn't want to pay free men, and might have hated the free men of the South for helping lose the war. Rich industrialists might have also brought in a few. Colonial Africa might have been a much worse place than the racist US at the time and might have looked attractive to some Africans even if they knew our society would not treat them as equals at the time. Deals might have been made between the US government and some of the Southern planters even before the end of the war to help them rebuild their economy and keep the South exporting the agricultural goods which gave the US its trade surplus. The replacements could have come from Liberia, or they could have been schooled in how to talk like ex slaves by Liberians. They could have been running from colonial oppression like the Belgian Congo or German Angola or tribal warfare, starvation, or disease. They would have paid to learn how to talk like Americans. If the government aided and abetted large southern landowners in re-establishing the nation's cash exports, they may also have aided them by getting Segregation passed into law until the slaves' replacements learned to speak without foreign accents. Maybe I'm obsessed with my theory but when I hear recordings of civil rights leaders speak of segregation when it was still in living memory, they seem to be hiding something. It is well known that the South tried to practice "Cotton Diplomacy" by embargoing its own cotton crop from Europe. There were also said to be vigilance committees of Southerners who blocked cotton exports in order to manipulate the value of certain bonds. They probably had to import at least some of their food even in good times because it may have made more sense to do so than to grow food on land that was well suited to more lucrative crops. If there was no money coming in, there would have been no way to buy food. The North also blockaded Southern ports which would have hampered all exports and imports. The rich plantation owners would have realized they should sell their slaves if they could. If they didn't get money for weapons, they were probably going to lose and have to give the slaves up for free. They knew they could always buy more slaves after the war even on credit because it was known the South was good for making money. The South would not be able to export goods grown by slaves until after they won the war. The slaves could have run both the Southern and the Northern blockades easier than other goods. Neither side was able to devote much manpower to the blockades. Bales of cotton and hogsheads of tobacco need to be loaded onto ships in ports but slaves could walk and be rowed out to waiting ships in small boats. They might have been sold throughout Latin America and the Caribbean. Perhaps the war would have ended sooner if this had not been taking place. The Emancipation Proclamation may have been an attempt to render the slaves less salable to governments that had not yet recognized the Confederacy, in order to deprive the Union's enemy of gold which they could use to buy weapons. Sherman's march may have also been an attempt to break the slave pens so the slaves could not be sold. It destroyed much of the South's economy so it would have worsened starvation. Sherman's soldiers probably weren't carrying or foraging enough food to feed all the runaway slaves. It may have happened after the Emancipation Proclamation but the slaves might still have been valuable on the black market.