Air pollution in ancient civilizations was not as severe as today but was still present. Most of it came from agricultural burning and copper mining.

There was a bit of water pollution, not as bad as today, but it was still prevalent because of sewage.

Most humans got their energy from farming, hunting, and fishing.

In Greece, people decided to cut fewer trees down and continue planting more to conserve trees.

Lead poisoning was an issue because tap water would be contaminated with lead in Rome and other places.

Water pollution was less of a problem during this time.

The Enlightenment inspired people to rethink concepts of liberty, equality, and individual rights. Secularism became popular during this time and people began to improve living conditions and their government. 

Thomas Malthus predicted that population would grow faster than food supply, resulting in famine and poverty.

New pollution affecting the new world includes household combustion devices, motor vehicles, industrial facilities, and forest fires. 

Sanitation became important because it prevented the spread of disease and was an indicator of illness and poverty in certain regions. 

During this time, there was a lack of clean air in cities due to air pollution from dust, human activities such as wood burning, and methane gas emissions from cattle and livestock. 

As new technologies were created during this time, there was a greater increase in water pollution. Town gas from coal would drip tar into the rivers, and vulcanized rubber plants discharged harmful chemicals directly into the streams. 

When the “Mother of the Forest”, a 311 feet tall tree, fell, its bark was stripped and shipped to England where it was put on display.

Social and political reforms such as civil service reform, food safety laws, and increased political rights for women and U.S. workers occurred during the Progressive Era. 

The purpose of the National Coast Anti-Pollution League, formed in 1922, was to address and combat the pollution of waterways, particularly focusing on oil dumping and its detrimental effects on marine life and public health.

People started to notice that smog was irritating them. World War II also caused people to believe that vehicles used for war caused pollution.

The Cuyahoga River erupted in flames after oil spilled into the river and it ignited.

 The USA Environmental Protection Agency was founded.

The Bhopal gas tragedy (1984) and Chernobyl nuclear disaster (1986)​​ occurred

Acid rain started becoming a problem in higher proximity, and the ozone layer started depleting rapidly

The Gulf War caused massive oil spills and burning oil, causing damage to the nearby natural environment

China constructed the Three Gorges Dam, and it caused a lot of controversy due to the resource use

During office, President Clinton signed the Roadless Area Conservation Rule, which stopped the construction of new roads, hence saving forests

The Bush presidency took a weird take on the issue of climate change by prioritizing technological advancement over mandatory regulations

Leaded gasoline had positive international support but later got banned due to a large sum of people finding out about the deteriorating environmental effects