September 11, 813: Charlemagne crowns Louis I “The Pious,” his only surviving son, as coregent of the Holy Roman Empire. Louis’s 26-year reign, though marked by civil war, was the longest of any medieval emperor until Henry IV (1056-1106). Deeply religious, Louis cleared the imperial court of pagan imagery collected by his father, sent his unmarried sisters to nunneries (partly to keep them away from scheming brothers-in-law), and performed public penance before Pope Paschal I for causing the death of his rebellious son Bernard, king of Italy.
September 11, 1226: The Roman Catholic practice of public adoration of the Blessed Sacrament outside of Mass spreads from monasteries to parishes.
September 11, 2001: In the early morning, 19 militants from the terrorist group, Al Qaeda, hijack 4 planes, aiming to crash them into major American landmarks. Two planes were crashed into the two towers of the World Trade Center. One plane was crashed into the Pentagon building. A fourth plane, thought to be bound towards Washington DC, crashed in a field in Pennsylvania after passengers, including Todd Beamer, a Christian father and graduate of Wheaton College, tried to fight back against the hijackers. Beamer’s words, “Are you guys ready? Let’s roll,” heard over an open phone line, became a rallying cry for many in the wake of the tragedy. The attacks claimed the lives of about 3,000 people.