Southern dialects originated in large part from a mix of immigrants from the British Isles, who moved to the American South in the 17th and 18th centuries, and the creole or post-creole speech of African slaves.Upheavals such as the Great Depression, the Dust Bowl and World War II caused mass migrations of those and other settlers throughout the United States.Little unified these older Southern dialects, since they never formed a single homogeneous dialect region to begin with.Some older Southern accents were rhotic (most strongly in Appalachia and west of the Mississippi), while the majority were non-rhotic (most strongly in plantation areas); however, wide variation existed.As of 2006, its Southern accent is strongly reported throughout the U. states of Virginia, North Carolina, South Carolina, Georgia, Alabama, Mississippi, Tennessee, Arkansas, Louisiana, and Kentucky, as well as most of Texas, eastern and southern Oklahoma, southern Missouri, southeastern Maryland, West Virginia, northern Florida, and southeastern New Mexico.The accent of some Midland American English (often identified as a South Midland accent) is documented as sharing key features with Southern American English, though to a weaker extent, including in northern Oklahoma, eastern and central Kansas, Missouri generally, the southern halves of Illinois and Indiana, southern Ohio, western Delaware, and south-central Pennsylvania.The Southern United States underwent several major sound changes from the beginning to the middle of the twentieth century, during which a more unified, region-wide sound system developed, markedly different from the sound systems of the nineteenth-century Southern dialects.
One historical English dialect spoken only by those raised in the Greater New Orleans area is non-rhotic and noticeably shares more pronunciation commonalities (due to very strong historical ties) with the New York accent than with other Southern accents.
This French dialect is spoken by many of the older members of the Cajun ethnic group and is said to be dying out.
A related language called Louisiana Creole French also exists.
Southern American English as a regional dialect can be divided into various sub-dialects, the most phonologically advanced (i.e., the most innovative) ones being southern varieties of Appalachian English and certain varieties of Texan English.
African-American English has many common points with Southern American English dialects due to the strong historical ties of African Americans to the South.