Also, generally, by the ex-slaves.
If I remember correctly, there was a disastrous attempt under Lincoln to colonize freed slaves somewhere in or around Haiti. Most of the colonists died of starvation or disease.
All such attempts foundered in practice due to the sheer cost of doing any such thing with 4M people, even if they were willing to participate.
The same reason, BTW, all attempts to do compensated emancipation never went very far. At a time when the entire federal budget for 1860 totaled $60M, the $3000M value of all the slaves was more than a little daunting.
Actually the slaves were worth ~$3B, not $300M. My bad. That’s 50 years worth of the prewar federal budget.