From 6 April to 17 May 1920, following military intervention to put down the Ruhr uprising, Frankfurt was occupied by French troops. The French claimed that Articles 42 to 44 of the peace treaty of Versailles concerning the demilitarisation of the Rhineland had been broken. In 1924, Ludwig Landmann became the first Jewish mayor of the city, and led a significant expansion during the following years. During the Nazi era, the synagogues of the city were destroyed.