This would be a sphere of influence. There have been instances of these throughout history, including in China, the US, etc.
<span>James Buchanan, Minister to Great Britain and former Secretary of State.Franklin Pierce, President of the United States.Stephen Douglas, U.S. Senator from Illinois.<span>Lewis Cass, Former U.S. Senator and 1848 presidential nominee from Michigan
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The German U-boats blocked British Isle and attacked merchant ships affecting the trading business of US with British, but at some stage the U-boats started to attack ships taking the lives of unarmed passengers, as with the Lusitania ship, which 120 American died. The Germans were asked to stop the attacks but they did not and many US ships sank, shedding off US citizens lives. The submarine warfare enraged the US neutrality which then turned against the German and declared war on March 1 in 1917.
The caste system. There was also a fifth group, untouchables, who were considered casteless.