A nephew of Napoleon I, Louis Napoleon Bonaparte (Napoleon III) was involved in two attempted coups of the French government, and sentenced to prison for life. He escaped in 1846 and fled to England. Returning in 1848, he was elected to the national assembly largely on the basis of his name, but later rose to become President of the Second Republic. In 1852, a national vote established the French Empire, with Napoleon III as Emperor, as he is shown on this 1856 coin. The sharp engraving on the obverse shows a distinguished profile in detail; the reverse the national shield and eagle, along with tiny images of a lion and anchor.
The edge reads, in translation, God Protects France. A classic coin in remarkably well-preserved condition.