Hi-5: History Today, March 31

1146 – French abbot Bernard of Clairvaux preached a sermon to a crowd at a council in Vézelay, with King Louis VII in attendance, urging the necessity of a Second Crusade.

1913 – Arnold Schoenberg conducted the Vienna Concert Society in a concert of expressionist music that so shocked the audience that they began to riot (depicted).

1930 – To avoid government censorship, Hollywood movie studios instituted their own set of industry censorship guidelines, popularly known as the Hays Code.

1970 – Nine Japanese communists armed with samurai swords and pipe bombs hijacked Japan Airlines Flight 351 en route from Tokyo to Fukuoka.