The modern Province of Cantabria was constituted on 28 July 1778 at Bárcena la Puente, Reocín.

The Organic Law of the Autonomy Statute of Cantabria was approved on 30 December 1981, giving the region its own institutions of self-government.

The rivers of Cantabria are short and rapid, descending steeply because the sea is so close to their source in the Cantabrian Mountains.

The region has a humid oceanic climate, with warm summers and mild winters.

Annual precipitation is around 1,200 mm at the coasts and higher in the mountains. Snow is frequent in higher zones of Cantabria between the months of October and March.

The great limestone masses of Picos de Europa also stand out in the southwest of the region: most of their summits exceed 2,500 m, and their topography is shaped by the former presence of glaciers.

Due to the gulf stream, Cantabria, as well as the rest of "Green Spain", has a much more temperate climate than might be expected for its latitude, which is comparable to that of Oregon.

This provoked a surge of eucalyptus - see Eucalyptus article on Spanish Wikipedia - plantations (and to a less extent of Pines) which often hid the illegal destruction of native forests, just as the spread of livestock farming had done in the past by the endemic conversion of forest into prairie.

This acts have been laxly controlled by the local councils or the central governments, in a process that clearly follows the saying: "Pan para hoy, hambre para mañana" (which translates as: "short-term gain, long-term pain").

The variation in the altitude of the region, which in a short distance ranges from sea level to 2,600 meters in the mountains, leads to a great deal of diversity in vegetation and a large number of biomes.

Cantabria has vegetation typical of the Atlantic side of the Iberian Peninsula.

Some zones of Picos de Europa, over 2,500 metres high, have an alpine climate with snow persisting year round. The mountainous relief of Cantabria has a dominant effect on local microclimate in Cantabria.

It is the main cause of the peculiar meteorologic situations like the so-called "suradas" (Ábrego wind), due to the foehn effect: the southerly wind coming down from the mountains blows strongly and dry, increasing the temperature closer to the coast.

Numerous authors, including Isidore of Seville, Julio Caro Baroja, Aureliano Fernández Guerra and Adolf Schulten, have explored the etymology of the name Cantabria, yet its origins remain uncertain.