What two periods were the earths average global warming temperatures the highest?

The Earth's average global temperatures were highest during two key periods: the Paleocene-Eocene Thermal Maximum (PETM) around 56 million years ago, when temperatures rose significantly due to massive carbon emissions, and the late 20th to early 21st century, particularly from the 1980s onward, driven by human-induced greenhouse gas emissions. Both periods saw dramatic shifts in climate, leading to significant ecological and geological changes.