This ring commemorates the German bombardment of Paris during the Franco-Prussian war of 1870-71. It is inscribed TOUS/ AUX/ DANGERS/ TOUS/ A L'HONNEUR/ 1870-1871 (United in danger, united in honour 1870-1871) and with the initials AM for Ave Maria.
Paris surrendered to the forces of General Bismarck on the 28 January 1871 after a prolonged siege.