Population growth in the land, especially in urban population was in part due to industrialization of the nation. The increasing factory businesses created many more job opportunities in cities and people began to flock from rural, farm areas to large urban locations. Minorities and immigrants added to these numbers.
In 1870, there only two American cities with a population of more than 500,000, but by 1900, there were six. Three of these namely Philadelphia, Chicago and New York had over 1 million inhabitants.
Because Mae Jemison became the first African American woman to travel in space
Hitler broke the Munich Agreement following the Nazi invasion of Poland in 1939 signaling greater expansion of Nazi territorial acquisitions in Europe. This sparked the outbreak of World War II.
The Sioux agreed to settle within a reservation in Black Hills of the Dakota territory in exchange for peace.
