September 26, 1460: Pope Pius II assembles European leaders, then delivers a three-hour sermon to inspire them to launch a new crusade against the Turks. The speech works, but then another speaker, Cardinal Bessarion, adds a three-hour sermon of his own. After six hours of preaching, the European princes lose all interest in the cause; they never mount the called-for crusade.
September 26, 1897: Charles C. Overton, a Sunday school superintendent at Brighton Chapel, Staten Island, spontaneously promotes the idea of a Christian flag. The Rally Day speaker hadn't shown up, so Overton gave an extemporaneous address on Christian meanings for the elements of the American flag. The red, white, and blue cross flag Overton later helped devise was first sewn around 1907 and continues to be used in some churches.
October 24, 1260: France's Chartres Cathedral, the purest example of Gothic architecture, is consecrated.
October 24, 1648: The Peace of Westphalia ends central Europe's Thirty Years War. Extending equal political rights to Catholics and Protestants (including religious minorities), the peace treaties also marked the first use of the term "secularization" (in discussing some church property that was to be distributed among the warring parties).