When all slaves were freed in the US, what did they do to survive? I’m guessing many didn’t own any land or have any money. Did most continue working for the same person who formerly owned them, but now receiving a salary? Where did they live?
What were slaves to do after being liberated from bondage was indeed a great question during the war and Reconstruction. Many Americans, North and South, believed that left to their own devices Blacks would simply give in to vice and license, and that they were naturally lazy. What a nonsensical thing to say about the people that built up the nation, but you know racism is not logical. But in any case, this prejudiced belief informed the decisions of the United States government in regards to Black labor.
During the war, the needs of the military took precedence over the needs of African-Americans. The Lincoln administration and the military commanders recognized that some sort of help had to be offered to the escaped slaves, nicknamed contrabands, for many were sick and hungry. The contrabands were initially put into filthy army camps were disease and mistreatment resulted in thousands of deaths. But soon, it was decided that the best thing to do with the contrabands would be to put them to work. Soon enough, the Union Army employed thousands of contrabands to clean, cook, build fortifications, infrastructure, etc, the "fatigue work" that White soldiers would have had to do otherwise.
But this was, of course, a temporary arrangement. Experiments on free labor took place in areas of the South occupied by the Union Army with large populations of freedmen. The South Carolina Sea Islands saw one of these experiments, with teachers and missionaries flocking to them as "emissaries of Yankee culture" that sought to uplift the freedmen through education and labor, allowing them to raise their own cotton and sugar to sustain themselves. Lincoln, towards the end of the war, would conclude that the Sea Islands experiment was “an earlier and happier consummation than the most sanguine friends of the freedmen could reasonably expect".
Previous to the Emancipation Proclamation, Lincoln pushed for several schemes whereby Freedmen would voluntary emigrate to Africa or Latin America. The Liberian scheme had already failed many decades ago, and plans for settlement in Latin America were similarly unsuccessful because the Latin American countries opposed African-American immigration. Only in Haiti was a brief experiment attempted when 453 colonists were taken to Île-à-Vache near Haiti, but the settlement was decimated by smallpox and bad administration and at the end the 368 survivors returned to the United States. Colonization schemes were already dying by then, for the Emancipation Proclamation had been issued and changed the nature of the war.
The Proclamation included a passage inviting Blacks to escape to the Federal lines and "labor faithfully for fair and reasonable wages". They were still being used to labor for the army, but the failure of colonization and the new conception of the war as a complete transformation instead of simple a struggle to restore the "Union as it was" meant that the place of freedmen in the United States after the war had to be contemplated. Accordingly, commanders in the field and the War Department started many more "experiments" on free labor. Grant, for example, appointed John Eaton as intendent of contrabands on the Mississippi Valley, a position he used to provide the freedmen with medicine, schools and put them to work at plantations leased to Northern businessmen or even to the freedmen themselves. Thus Davis Bend, Jefferson Davis' brother's plantation, was given over to the slaves that had worked the land with the intent to create a "Negro Paradise".
The developments were similar in Louisiana, where General Banks was attempting to create a Reconstructed Louisiana of Free Labor. Early on, he simply declared slavery to be "inoperative and void" and started a labor system that would guarantee the "sanctity of the family, education for their children, the end of corporal punishment, and payment of reasonable wages" that Freedmen desired and identified with freedom. But military needs and prejudice regarding the capacities of the freedmen made the army prioritize putting freedmen to work rather than upholding their rights. Thus, the Army instituted a series of regulations that coerced freedmen into accepting yearly contracts, permitted physical punishment, instaured a pass and curfew system that limited Blacks' freedom of movement, and fixed wages instead of allowing Blacks to freely negotiate them. Free Labor this was not, and the Black community of New Orleans bitterly denounced the system as "Banks' oligarchy" and a system that kept Blacks "chained to the soil", to be exploited by “avaricious adventurers from the North.”
In the immediate aftermath of the war, the question of Black labor remained. Since military and political necessities, like raising cotton for Northern industry or using contrabands as military laborers, were no longer a concern, the salient question was how Blacks were going to sustain themselves. The Republican aim was the construction of a South of free labor, where Black men would compete on equal grounds with Whites. But poverty, disease and inequality still tormented African-Americans, and these would have to be remedied first if a true free labor economy was to be erected in the South. The Freedmen's Bureau was tasked with this "herculean" duty, which entailed not only providing the freedmen with temporary assistance, but educating them, protecting them from White terrorism and the unequal governments of Presidential Reconstruction, and maintaining good relations with a formerly rebel population that saw Black equality as a terrible foreign imposition. Couple this with inadequate founding, resources and manpower, an ineffective Army purged of sympathetic officers and an outright hostile President, and you have to wonder how the Bureau achieved anything at all.
Nonetheless, the Bureau did help freedmen survive until they could start working on equal terms. It provided rations of foods, constructed hospitals to provide medical treatment, provided education and took care of the insane, orphans and the disabled, and offered at least a modicum of protection and impartial judgement to the freedmen. The Bureau was always conceived as a temporary institution, and the head of the Bureau and its agents were always concerned with not becoming a "pauperizing agency". Blacks, they insisted, had to "feel the spur of necessity, if it be needed to make them self-reliant, industrious and provident." To be simply reduced to wards of the state would emasculate them, and even the Black community believed asked for no favors from the state, only equality to White laborers.
In the aftermath of the war, Blacks showed that they did feel the spur of necessity by building their own schools, churches, and seeking to work. They were not opposed to labor as malignant Southerners claimed, the freedman just asked for "justice, impartial justice, and we believe, he will work better as a freedman than he did as a slave". For the first time Blacks had the upper hand in the labor question, as plantations desperately needed labor and offered generous terms in order to entice Blacks to labor. "Planters are literally cutting one another’s throats", reported one Southerner. Amidst the flux of revolution, Blacks hoped that the government would offer them land taken from the slaveholders, and war-time free labor experiments and events such as General Sherman's Field Orders 15, the famous "40 acres and a mule" orders, reinforced these hopes. Some couldn't wait and took abandoned plantations for themselves. The Freedmen's Bureau, with 850,000 acres of abandoned and confiscated land, seemed ready to advance these radical goals and build up a black yeomanry.
Unfortunately for them, Lincoln was assassinated and Johnson took over. Despite speeches about how treason was to be made "odious" and traitors punished, Johnson quickly decided that the most important goal was to force Blacks back to the plantations and hand control of the South to more or less the same people. These respetable gentlemen of Whiggish background were economically progressive, but they were still White Supremacists who had no desire to bring true change to the South. Johnson purged the Bureau of its "abolitionist" officers and gave back the land to its former owners, sometimes using the army to violently expulse the freedmen and force them to sign labor contracts for good measure. Working under the assumption that Blacks would not work unless forced to under White supervision, the governments of Presidential Reconstruction also sought to recreate the social and economic circumstances of slavery through "wise laws".
These infamous Black codes did much to impair the capacity of Blacks to labor in equality in a free labor market. They forced them to sign yearly contracts under threat of being imprisoned as "vagrants", put limits on their mobility and even behaviour (requiring, for example, them to be "disciplined" and "respectful", code words for submission to Whites), limited economic opportunities by making enticement (offering a better wage to someone already employed) a criminal offense and prohibiting fishing, hunting, or grazing on land one did not own so that freedmen could only support themselves by working on plantations. The Army did overturn some of the worst provisions, but they also were more preoccupied with the question of whether Blacks would work than these injustices, so it often helped along by rounding up freedmen to work on plantations or enforcing inequality. For example, General Tillson declared Blacks to be “lazy, worthless vagrants,” and accosted school children, telling them to go and pick cotton instead of learning. Even the Bureau "seemed to consider black reluctance to labor the greater threat to its economic mission".
This question comes up regularly. Look at the contributions of /u/SisterChenoeh, /u/EdHistory101 and /u/lyle_lanly in this thread.