Historians work to methodically dissect the past to help us understand the present and avoid making similar mistakes in the future.
The base job of a Historian is to break down a historical events into parts to understand how the historical event or historical arc could have occurred as it did. This could range from "Why did the Japanese bomb Pearl Harbor" to "Why did the Union win the Civil War"
Each question has answers that can help future generations understand the implications of their actions.
The Inca and Aztec empires were heavily impacted by European exploration and colonization. The first impact was that when Europeans reached the Americas, the Incas and Aztecs were conquered which killed thousands of them and enslaved the ones that survived.
The first astronomer to state the fundamental laws of planetary motion, Kelper was also known for his works in geometry, optics and philosophy.