Siege of Weinsberg, within the then-Holy Roman Empire, was a decisive battle between Welfs and Hohenstaufen. During it the Welfs for the first time changed their war cry 'Kyrie Eleison' for their party cries. The Hohenstaufen used the 'Strike for Gibbelins' war cry.
On the death of Lothar II in 1137, the Welf Henry the Proud, heir of the patrimony of his deceased father-in-law, and possessor of the crown jewels, stood boldly forward as a candidate for the imperial dignity. But the local princes, opposing him, elected the Hohenstaufen Conrad III in Frankfurt, on February 2, 1138. When Conrad gave the Duchy of Saxony to Count Albert the Bear, the Saxons rose in defence of their young prince, and Count Welf of Altorf, the brother of Henry the Proud, began the war.
Exasperated at the heroic defence of Welfs, Conrad III had resolved to destroy Weinsberg and imprison its defenders. He however suspended the last assault, after negotiating a surrender which granted the women the right to leave with whatever they could carry on their shoulders. The women eschewed their possessions, and carried their husbands on their shoulders. When the king saw what was happening he laughed and accepted the women's clever trick, saying that a king should always stand by his word. This became known as the "Loyal Wives of Weinsberg" (Treue Weiber von Weinsberg) episode. The castle ruins are today known as Weibertreu ("wifely loyalty") in commemoration of the event.