The origins of the name 
The family name Hamelin, like other names of the same root (Hamel, Hameau, Duhamel, Hamelet, Hamelot...) designated the "man who lived outside the village", in a hamlet. 
About 8,080 bearers of this name have been counted in France today and they are found primarily in the West (Maine, Loire Valley, Brittany). 
 

The hamelins in the Loire Valley 
More than 13% of the bearers of this name in France are found in this region. The department having the greatest number is Sarthe (264 families) followed by Maine-et-Loire (168), Indre-et-Loire (64), Loir-et-Cher (26), Vienne (18), Cher (8), Indre (7) and Deux-Sèvres (6). 
 

A friend of Josephine... 
Antoine-Marie-Romain Hamelot (1770-1855), maternal grandson of a farmer, became treasurer of the Berry region and later of Tours. Through his Creole wife, he was a friend of Josephine de Beauharnais. It was thanks to her that he was given the responsibility of supplying the needs of the Italian army and he thereby established a monopoly of the fisheries of Pô. In 1831, he became director of the colonization of Algeria. 

... and a "naughty" wife 
The wife of this man, Fortunée Hamelin, formerly Lormier-Lagrave (1776-1851), was one of the three "marvelous women" of the Consulate and of the Empire who were most in the public eye. Surnamed "the naughtiest person in France", she collected lovers, among whom were Bonaparte and Chateaubriant. Her husband, who became weary of it all, asked for a separation in 1802.  Afterwards she lived on monthly subsidies she received from the police for becoming a spy on the payroll of Fouché.