Orange symbolizes the warmth of autumn and the last of harvest season, while black represents the cold, dark, and long winter.
When having pride of a certain country, it is called nationalism.
Too much nationalism can cause problems, one of the causes of WW1 was nationalism.
How the revolution lead to the need for reform is that because the industrials ( cars, clothing, farming, mechines) many people were put into had working conditions, long work hours, child labor, and low wages. People sarted making reforms to be we to control business poor practices.
True, Nativists were an anti-immigrant group that held racist views of new immigrants.