The Franco-Prussian War was brought about by rising tensions between France and Prussia in the 1860s. France, under Emperor Napoleon III, was determined to check the growth of Prussian power and avenge what it saw as a series of diplomatic humiliations. Prussia, under Chancellor Otto von Bismarck, believed that a Prussian-led war of the German states against France would be a decisive act leading to creation of a unified German empire. The conflict began on July 19, 1870, when France declared war. The French army proved woefully unprepared and suffered a disastrous defeat at the Battle of Sedan, leaving open the road to Paris. By September 19, the Germans had completely surrounded the city and begun a siege that was to last more than four months. Cut off from supplies from the countryside, the Parisians held out by eating dogs, cats, and even most of the animals in the Paris zoo. The trees on the Champs-Elysées and in parks were cut down and burned for fuel. On January 5, the German armies began a bombardment of the city, which lasted several hours each night for a period of 23 nights. About 12,000 shells fell on Paris neighborhoods, killing some 400 people. Paris surrendered on January 28, effectively ending the war. Siege de Paris: 1870–1871 (The siege of Paris: 1870–1871) is an album of 110 photographs taken by Auguste Bruno Braquehais (1823–75), a French photographer and pioneering photojournalist, documenting the siege and the effects of the bombardment. The album is from the Thereza Christina Maria Collection, which was assembled by Emperor Pedro II of Brazil and given by him to the National Library of Brazil.