What is a historical fact that would sadden most people if they found out?

Sadly, history is full of tragic events that could sadden anyone who learned about them. One such event is the Armenian Genocide, which occurred during World War I. The Ottoman Empire, which was allied with Germany and Austria-Hungary, systematically killed an estimated 1.5 million Armenians between 1915 and 1917. The genocide was a result of the Ottoman government's fear of Armenian nationalism and its desire to create a more homogenous Turkish state. Armenians were rounded up, deported, and massacred in a campaign that shocked the world.

Another historical event that would likely sadden most people is the Rwandan Genocide. In 1994, the Hutu majority government in Rwanda began a campaign of violence against the Tutsi minority. Over the course of 100 days, an estimated 800,000 Tutsis and moderate Hutus were killed in a brutal and bloody massacre. The genocide was sparked by the assassination of the Rwandan president, Juvénal Habyarimana, and was fueled by ethnic hatred and political opportunism.

The Holocaust is another historical event that would undoubtedly sadden most people. During World War II, the Nazi regime in Germany systematically murdered an estimated six million Jews, as well as millions of other people, including Roma, homosexuals, and disabled people. The Holocaust was a horrific crime against humanity and a reminder of the dark side of human nature.