Their relations were marked by frequent labor unrest and violence that disrupted deliveries.
Because of the frequent political unrest in São Tomé, the capital was moved in 1753 to Santo António on Príncipe, whose harbour was the site of much activity.
In view of frequent political unrest the city was named in 1996 as one of the most dangerous cities in the world.
Under pressure to expand local economies, officials have stepped up seizures and sales of farmers' land, a frequent cause of unrest.
"A source of vehement disagreements, a security risk for all who attend it and a frequent focus for unrest and protest, the Quidditch World Cup is simultaneously the most exhilarating sporting event on earth and a logistical nightmare for the host nation," Rowling writes.
The plan is to replace all fees with a uniform tax, but this has encountered strong resistance among rural governments, which are worried about losing even more of their revenue.The result is growing rural discontent, with ever more frequent outbreaks of unrest.
Compare our record of immigration with countries in Europe, where race riots and social unrest are frequent occurrences.
The frequent flares of social unrest in China could spread, and the government could decide that its short-term problems take precedence over its long-term ones.
The volatile but oil-rich Eastern Province, home to many of the Sunni kingdom's sizeable Shia minority, has witnessed frequent bouts of violent unrest in the past year.
The abandonment of some of China's most fertile land reflects the economic difficulty that has engulfed central China in recent years, trapping millions of farm families and leading to frequent reports of rural unrest.
