Which country was the first to introduce vehicle registration plates?

The first motor vehicle registration plates were introduced in the Department of the Seine, France, by a police ordinance of August 14, 1893. The scheme was extended to the whole of France by a decree of September 30,1901, which applied to all vehicles capable of exceeding 30 kilometres per hour (about 19 mph). By that time registration plates were already mandatory throughout Belgium.
(New Shell Book of Firsts)

Many people credit the Dutch for inventing number plates. While the Netherlands Vehicle Authority (Dienst Wegverkeer) did introduce the first ever nationally registered license plate system on 26 April 1898, the concept itself was conceived five years earlier in France. The now defunct the Department of the Seine in Paris took matters into their own hands when automobiles began to crowd the streets of the city. On 14 August 1893, the department passed the Paris Police Ordinance which introduced revolutionary requirements such as driving licenses, vehicle registrations and unique identifier tags. These identifier tags, which referenced a vehicle’s registration and ownership details, were required to be displayed on the left side of every vehicle using the streets of Paris.

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