This has happened since the industrial revolution that builds energy sources derived from coal, petroleum and gases that dispose of gases in the atmosphere, such as carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O).
The industrial revolution started in the 18th century. But the climate change wasn't noticed until the 1970s or so. The gas emissions before that were not very significant. The issue worsened only during the 1970s, when the burning of fossil fuels reached a peak.