Answer: Most likely the industrial revolution.
Explanation: The use of machines in production became more and more prevalent, eventually many factories were built in cities which caused pollution therefore making the air gross.
What do mean be more Specific
Why did the War of 1812 end?
Answer: A large British army under Sir George Prevost was thus forced to abandon its invasion of the U.S. northeast and retreat to Canada. The American victory on Lake Champlain led to the conclusion of U.S.-British peace negotiations in Belgium, and on December 24, 1814, the Treaty of Ghent was signed, ending the war.
History Channel › this-day-in-history
War of 1812 ends - HISTORY
Answer:
important so that people can elect there own leader and Be independent
