The reason why North and South American societies are considered to be the most diverse in the world today is because of their History. North America, especially the United States, is an immigrant country, it received thousands of immigrants from very diverse backgrounds in the XIX century: German, Chinese, Italian, Irish, Eastern European, etc. While South America is a mixture of different races: the Spanish conquistadors had children with the native peoples like the Aztecs or the Incas, plus the black slaves that were brought from Africa.
Due to diversity of multiculturalism and diversity, they are considered as more diverse in the society.
They have more than 560 official languages which are spoken in United States. And there are more than 1000 languages which are spoken in the societies.
As Americans are cultural and there is on another factor which make them diverse id immigration. So, due to different cultures, casts and languages these societies become more diverse in the whole world.
The South’s economy during the Civil War deteriorated;
The civil war freed the slaves consequently getting rid of the majority source of the Southern work force. Moreover, the civil war saw the destruction of a great deal of South's infrastructure including; the destruction of railroads which resulted in short-term damage of the South's economy.
Economically, Southern Germany is the strongest part of Germany, with Baden-Württemberg and Bavaria being the powerhouses of manufacturing, especially in the automobile and machinery industry.