Republicanism in the United States
When they were writing state and national constitutions, the Americans used ideas from Montesquieu, an 18th-century French political thinker.  Montesquieu wrote about how the perfect British constitution would be "balanced."  The idea of a balance of power (also called "checks and balances") is a very important part of the Constitution.  It is one of the strategies the Founders used to make sure their government would be republican and protect the people from government corruption.