The answer is economic growth .
<span>Spain in the 1500s, when they traded with the Native Americans some play toys....</span>
In the morning with the first rays of the sun, the peasant woke up in his small house, which was in a small village consisting of 11 courtyards. A big friendly peasant family gathered at breakfast: A peasant with his wife, 4 daughters and 6 sons. Having prayed, they sat down for wooden benches. At breakfast, there were grains cooked in a pot, on a home hearth. After breakfast peasant should work to provide food to the knights and nobles.
Almost all the children of the peasant have already worked as adults. Only the youngest son, who barely passed 5 years, could only graze geese. The harvest was in full swing. All day peasant with his family worked in the field, making only one break for lunch. In the evening they came home very weary. After supper, the peasant helps his wife in feeding the pigs and milking the cow. After that, the peasant began to make barrels for water. After sunset, everyone went to bed. Mother and father on a wide wooden bed, children on benches at walls which have covered with hay. Tomorrow morning the peasant with his family was going to getting up early again and working hard again...
World War II expanded African Americans' economic opportunities.
Due to the lack of manpower, since many men were in the front line, and with the country needing to increase its production to maintain the expenses of the war, World War II was a great opportunity for many African American enter the labor market in positions that until then were only obtained by white citizens.
Due to these reasons, from the entry of the United States into the war began the process called "Second Great Migration", by means of which many African American left their agricultural works to move to the northern cities of the country.
At the end of the Second Great Migration, African-Americans constituted a strongly urbanized group. More than 80% lived in cities and only 53% remained in the southern states of the USA, while 40% lived in the Northeast and the Great Lakes area and 7% in the West.
Although African Americans were offered jobs in the auxiliary industry during World War II they were often dangerous positions.