The plaque, that includes an image of an eagle, tells us:
Erected by the
Napoleon III
lived here
1848
Society of Arts
The Biography website tells us about Napoleon III:
Napoleon III, the nephew of Napoleon I, was emperor of France from 1852 to 1870. His downfall came during the Franco-Prussian War, when his efforts to defeat Otto Von Bismarck ended in his capture.
Born in 1808 in Paris, France, Napoleon III, the nephew of Napoleon I, grew up in exile—the year 1815 marked the end of Napoleon I's reign. However, Napoleon III was determined to regain the French throne. He began his quest in 1832, writing various political and military tracts in an effort to make himself and his ideas known. After a failed coup attempt in 1836, he was exiled again. After the Revolution of 1848, in 1850, Napoleon III was elected president of the Second Republic. He served in that position until 1852, when he was made emperor—a position he held until 1870, when the disastrous Franco-Russian War led to his capture. He was deposed and sent to England, where he died in 1873.
Louis-Napoleon lived in the United Kingdom until the Revolution began, in February 1848, and a new republic was established. He was then free to return to France, which he did immediately, but was sent right back to England by the provisional government because he was seen by many as a distraction to the settlement of a new government. Some of Louis-Napoleon's supporters, however, organized a small Bonapartist party and nominated him as their candidate for the Constituent Assembly, which was being brought together to draft a new constitution.
Louis-Napoleon won a seat and, in mid-1848, yet again returned to France, where he quickly began hatching a plan to run for the presidency. Because the Bonaparte name carried obvious weight in France, Louis-Napoleon captivated the voters as he evoked Napoleonic memories of national glory, promising to bring back those days with his administration. He also managed to succeed in promoting himself to literally every group of the population by promising to ensure the advancement of their particular interests, depicting himself as "all things to all men."
When the constitution of the Second Republic was finalized and elections for the presidency were held in December 1848, Louis-Napoleon won a surprising landslide victory, taking nearly 75 percent of the vote.
Napoleon III saw France's dominance in Europe eroded by Prussia's decisive victory over Austria in the Austro-Prussian War during the summer of 1866, and in 1870, when goaded by the actions of Prussian prime minister Otto von Bismarck, Napoleon III began the Franco-Prussian War (also called the Franco-German War).
The war was an unmitigated disaster for France and for Napoleon III personally, and it was instrumental in the creation of the German Empire, which would replace France as the major land power on the European continent until the end of World War I. During the Battle of Sedan in July 1870, Napoleon III was captured by the Germans. He was deposed two days later, and the Third Republic of France was declared.
Released by the Germans in 1871, Napoleon III moved to England, where he would spend his final years. He continued to write, and even thought of returning to France to regain his throne. Less than three years after his release by Germany, Napoleon III underwent an operation to extract bladder stones. He died shortly thereafter, on January 9, 1873, in Chislehurst, London, England.