The poor standing of Leopold the 2nd is most probably attributed to the role he had in the extermination of huge amounts of people in Belgian colonies at the time. This wasn't known at the time, but today we known that Leopold the 2nd had ordered a genocide over the Congonese people.
I believe it was when small and large States decided to have an upper and Lower house. the lower house, house of rep, was to have the number of rep. be based on population. while the upper house, the senate, was made to give all states an equal representation in the government. this being based on statehood ,which earned two senators, and did not take population into account into choosing the number of senators.
Probably the invention of Papyrus (paper)
Constantine moved the capital of the Roman Empire because of how dangerous it was to live in.
