Romanticism came as a reaction to enlightenment. The ideas of nationality and homeland started developing more and a pride in being a member of a country started growing. This led to numerous new revolutions since people wanted to be independent and have their own countries and countries like Austria-Hungary and the Ottoman Empire lost huge amounts of influence.
The corruption within the communist Chinese government, lack of freedom of speech, press, and restriction on political participation. Inflation and the democratic movement in Eastern Europe are triggers of the incident.
The most surprising thing for me personally was the set up of the trenches, there is a very good system where the front line is the first to attack or be attacked while the others are there as backups. If someone were to get hurt within the first trench, there are easily accessible routes for the soldiers to take to retreat to safety, on the contrary, if the front lines were in need of any reinforcement whatsoever, there is a clear way to travel for the soldiers to get more ammunition or man power.
The main characteristic of the absolute monarchies was the existence of a king who had absolute political control. This meant that there were no laws, division of powers, or any other form of control over the decisions or actions of the monarch.