The Mongol invasions of Japan failed because Typhoon winds destroyed the Mongol fleet. The Mongols failed to conquer Japan even though they had successfully conquered the much larger land of China and also Korea. The typhoons that saved Japan did not even happen just once but twice ! Both times that the Mongols set out to conquer Japan, their fleets were destroyed by typhoons. Japan was geographically in luck and also helped by nature.
In his book, A People's History of the United States, Howard Zinn cites examples from US colonial history of the gap between rich and poor in colonial life.
A key study cited by Zinn examined tax registers from Boston, showing that the top 1% of the population held 25% of the wealth in 1687, and that by 1770, the top 1% of property owners in Boston owned 44% of the wealth. The study also noted that the bulk of Boston's population were not property owners. The percentage of adult males in Boston who owned no property doubled between 1687 and 1770 (from 14% to 29%).
Zinn cited additional items, regarding overcrowding of poorhouses (giving a notable example from New York) and a general increase throughout the colonies of the "wandering poor" who had no real means of support. He also cited examples of workers' strikes against employers in the colonies because of low wages.
The main effect of the systems of sharecropping and debt peonage put in place in the South after the Civil War was that the African American people were prevented from leaving the very plantations where they had worked as slaves. The African Americans were bound to the land since they were buying the land through sharecropping.
