Seine was the former department of France encompassing Paris and its immediate suburbs. It is the only enclaved department of France at that time. Its prefecture was Paris and its INSEE number was 75. The Seine department was disbanded in 1968 and its territory divided among four new departments: Paris, Hauts-de-Seine, Seine-Saint-Denis and Val-de-Marne. General characteristics From 1929 to its abolition in 1968, the department consisted of the City of Paris and 80 surrounding suburban communes. It had an area of 480 km² (185 sq. miles), 22% of that area being the City of Paris and 78% being suburbs. It is the only enclaved department in France. It was divided into three arrondissements: Paris, Sceaux and Saint-Denis. For most of the Seine department's existence, its prefect also exercised direct authority over the City of Paris as well. As a result, Paris was the only commune without a mayor; it had theoretically less autonomy than the smallest commune. History Formation Seine was created on 4 March 1790, as the department of Paris (Département de Paris). In 1795, it was renamed as the department of Seine (Département de la Seine) after the Seine River flowing through it. At the first census of the French Republic in 1801, the Seine department had 631,585 inhabitants (87% of them living in the City of Paris, 13% in the suburbs) and was the second most populous department of the vast Napoleonic Empire (behind Nord), more populous than even the dense departments of what is now Belgium and the Netherlands. With the growth of Paris and its suburbs over the next 150 years, the population of the Seine department increased tremendously. Dissolution By 1968 it contained 5,700,754 residents (45% of them living in the City of Paris, 55% in the suburbs), making it by far the most populous department of France. It was considered that the Seine was now too large to be governed effectively. On 1 January 1968, it was split into four smaller departments: Paris, Hauts-de-Seine, Seine-Saint-Denis and Val-de-Marne. The break-up of the Seine department involved the following changes: The city (commune) of Paris was turned into a department in its own right, with no other communes inside this department. The official number 75 which was used for the Seine department was given to the new Paris department. To the south and southeast of the city, 29 communes of the Seine department were grouped with