I just finished a part of the book "The Americas" by Sylvia R. Frey and Betty Wood which describes how slaves found it hard to communicate due to cultural and language barriers between them. These barriers persisted which helped the white slave owners since the slaves couldnt organize and revolt.
So the question is when and how did the slaves learn English, and if they did before the Civil War why didnt they revolt?
EDIT: There were barriers since the slaves were drawn from many different regions in Africa which were all culturally diverse.
Language Learning
Humans are natural language learners even as adults. Slave masters would have to give orders and some slaves would be taught more english than others because they were house servants, right? Even if slaves were systematically prevented from formally learning english, it would have been impossible to keep the language from them completely.
So simple words were learned first. Then once commonalities were established between all the different languages being spoken within a given population, a pidgin would form, basically a rough amalgamation of unrelated languages brought together to form a common system.
http://en.wikipedia.org/wiki/Pidgin
The children of these slave would be born into a population speaking this common tongue and after some time the language would form into an actual creole, a much more functional language system with uniform rules of syntax and grammar, etc.
http://en.wikipedia.org/wiki/Creole_language
Sorry I don't have dates for you, as I'm not a historian, but this is the process that happens everywhere language speaking groups come together to form communities. It usually happens over the course of a couple generations.
Revolt
There were cases of slave revolt before the American Civil War. Haiti is a good example. http://en.wikipedia.org/wiki/Haitian_Revolution
Why something similar didn't happen in the Unite States... well I'll leave that to the other fine gentlemen and ladies of this sub to lend their considerable knowledge.
Edit: More interesting studies! AAVE refers to African American Vernacular English.
"The creole origins issue is the older issue. The earliest linguists to suggest the possibility that AAVE had pidgin or creole roots were Schuchardt (1914), Bloomfield (1933:474), Wise (1933) and Pardoe (1937).2 The case was articulated in more detail by B. Bailey (1965) and repeated in Hall (1966:15). It was vigorously championed by Stewart (1967, 1968, 1969) and Dillard (1972, 1992), and it was subsequently endorsed by Baugh (1979, 1980, 1983), Holm (1976, 1984), Rickford (1974, 1977), Fasold (1976, 1981), Smitherman (1977), Edwards (1980, 1991), Labov (1982), Mufwene (1983), Singler (1989, 1991a, 1991b, to appear), Traugott (1976), and Winford (1992a, 1992b, 1997), among others. Arguing against the creole hypothesis, and asserting instead that the speech of African Americans derives primarily from the dialects spoken by British and other white immigrants in earlier times (hence the label "dialectologist") were Krapp (1924, 1925), Kurath (1928), Johnson (1930), Brooks (1935, 1985:9-13), McDavid and McDavid (1951), McDavid (1965), Davis (1969, 1970), D'Eloia (1973), Schneider (1982, 1983, 1989, 1993b), Poplack and Sankoff (1987), Poplack and Tagliamonte (1989, 1991, 1994), Montgomery (1991), Tagliamonte and Poplack (1988, 1993), Montgomery et al (1993), and Ewers (1996), among others. It should be added that positions are not always as polarized as these lists of creole proponents and opponents might suggest. For instance, while McDavid and McDavid (1951) felt that most AAVE features came from White speech, they recognized creole influence in the case of Gullah, and urged careful study of African and creole languages to see whether AAVE features in other areas might be traced to these. Similarly, Winford's (1997) paper is self-described as written from "a creolist perspective"--but it is one which allows for considerably more influence from British and other white dialects than creolists like Stewart and Dillard would concede. And Mufwene (1992:158) argues that "neither the dialectologist nor the creolist positions accounts adequately for all the facts of AAE" and that new intermediate positions are necessary."
if they did before the Civil War why didnt they revolt?
As others have pointed out they did. A few factors that contributed to the comparative lack of revolts.
1- Slaves in the United States were often born in the United States. This meant they tended to have families who would be impacted by any potential revolt. Conversely slaves imported into the West Indies and Brazil were young men and women captured in warfare in Africa (and there were more men than women). These young men often had no connections which meant they had nothing to lose
2- Slaves in the United States often developed closer relationships with whites. This took on the form of adopting language, religion etc.. Because of the longer lifespan there were often several generations of whites and blacks that had lived together, often interrelated as well.
3- Working conditions were better in the United States. Early State and National bans on the importation of slavery, coupled with a milder climate, and less brutal working conditions (along with slavery being generally not as productive as the West Indies sugar plantations) meant that slaves had less reasons to revolts.
4- Slaves in the United States lived Longer- Tied to number 3, slaves in the West Indies often had a lifespan of only a few years. This gave them few reasons not to revolt. Other means of controlling slaves in the United States, such as manumission, thus became defunct. Why labor in the eventual hope of manumission when you will likely be long dead.
5- The United States had a white majority. The West Indies had a black super-majority. This meant that any revolt had an extremely low chance of success in the long term for the United States.
6- The geography did not favor slave revolt. Unlike say Jamaica and Brazil which had difficult interiors, and eventually did have sizable runaway slave populations (in the case of Jamaica the Maroons were even able to fight the British to a standstill) the United States did not have large tracts of inhabitable land in the interior. There were of course some exceptions notably in the Southern swamps, and especially in Florida . But coupled with the huge white population there were few places that slaves could feasibly escape to.
why didnt they revolt?
John Green's US History crashcourse Slavery episode pointed out that one reason US slaves didn't engage in (perpetual, violent) rebellion is that it made their situation worse. The backlash to each rebellion was harsher controls, and group punishment.
But they always resisted: by having families, worshiping, building community. The efforts to dehumanize them (and blame them for their condition) were ultimately and emphatically resisted by every act which demonstrated their humanity: from suffering to celebration; from hate and anger to love and spirituality.
But the assumption that "they didn't revolt" is offensive for a very good reason: this idea (though inaccurate) has been used to blame African Americans for not becoming free sooner. It is also a way of suggesting that slavery "wasn't that bad". You probably didn't have that intent, but the language you used plays into an existing narrative that does have an intent to marginalize. Please be conscious of how your words shape the perception of other people's situation.
As an aside, you may as well ask why every prison in America isn't in a state of constant rebellion; what, pray tell, does rebellion offer a prisoner in our modern jails? Freedom? I hardly think so.
I think the original question is legitimate, and I don't know the answer. I'll point out that children acquire language through exposure. So I'd expect that a common working language among slaves and overseers would take about 1 generation to form, even if it was only a creole. But again, that is only speculation on my part, and not based on any historical sources.
Slaves originated from a variety of places and were brought over by a variety of European nations. Different parts of the country imported slaves from different areas as well. Some of them would have already known English (or Dutch, French, etc) from prior plantations in the West Indies, some of them would not speak a word. I think the first slaves in New York were creoles, so they would have spoken English with no trouble. The Carolinas brought slaves mainly from Barbados, as another example.
Assuming we're talking about someone captured with no prior contact to Europeans, the explanation given by Ira Berlin in Many Thousands Gone is that it depends on the task. If you're being sent to work rice or cotton, it doesn't matter if you speak the language. You just worked and struggled on. If you're a carpenter, horsemen, driver, or other complex task you're going to be exposed to the language more and picking it up from the people around you.
Importing slaves into America was banned in 1807 because of fear about the rising population of slaves. By the time the Civil War came around they would all have been born on American soil and fluent in English.
I believe there are good examples in the book Mammon and Manon in Early New Orleans: the first slave society in the deep south, 1718-1819 by Thomas Ingersoll. Books on New Orleans slave society are good on this subject in general.
Read the book called "The Book of Negroes" by Lawrence Hill. It's about a slave girl who is snatched from her village, taken to North Carolina, where she learns English and Math, etc. Brilliant book, in my opinion.