Their most important contribution was founding of the current-day provincial capital, Madinat-al-Faray (Guadalajara, from Arabic وادي الحجارة wādi al-ħajāra, "streambed/valley of stones"), which was established by the Berber captain al-Faray, remembered for overcoming the Christians in the 9th century.

With the conquest of Cuenca and Alarcón at the end of the 12th century and the victory at Las Navas de Tolosa in 1212, the entire territory of Guadalajara was again in the hands of the Castilian Christians.

They centralized the authority which had developed in the church, the military and the nobility ostensibly to earn income for fighting the infidels by reselling the territories they had gained.

The Mendozas who succeeded in acquiring substantial territories built a fortified palace in Pastrana and extended their influence over Sayatón, Escopete and Albalate.

[2] Under the Mendozas, the city of Guadalajara prospered in the 15th and 16th centuries, attracting writers, historians and philosophers, bringing it the name la Atenas alcarreña (the Alcarrian Athens).

Encouraged by the Renaissance, Íñigo López de Mendoza, 1st Marquis of Santillana, (1398–1458) not only built palaces, churches and monasteries but developed a large library of Greek and Latin volumes.

In the 16th century, his namesake Íñigo López de Mendoza, 4th Duke of the Infantado, (1493–1566) went on to found an academy in the city, attracting additional writers.

Pastrana also prospered during the Renaissance under the leadership of Ruy Gómez de Silva (1516–1573) with the establishment of Latin and choir schools.

With the death of Ruy's widow, Ana de Mendoza in 1592, the nobility moved to Madrid, causing the province to lose the high status it had achieved.

[2] In the early 18th century, under the War of the Spanish Succession, the city of Guadalajara and the province's main towns all suffered considerable damage.

During the War of Independence, French troops caused extensive damage to towns in the province, especially Molina where over 600 buildings were destroyed by fire.

Further military installations followed, culminating at the end of the century in the establishment of the Airship Regiment which led to a range of early exploits and experiments.

The population increased slightly, while further improvements resulted from the influence of the wealthy landowner and politician Count of Romanones who was the representative for Guadalajara from 1886 to 1936.

After fighting on the Republican side during the Spanish Civil War, the province was given little attention by the successive governments of Francisco Franco until the late 1950s when plans for moving industrial development out of Madrid began to favour Guadalajara and the Henares corridor.

While new industries and improved communications brought prosperity to Guadalajara, Torrejón, Alcalá, Azuqueca and Yunquera de Henares, it also caused drastic decreases in population in rural areas.

[10] The province, given its wide and varied geographical features, has a range of different weather conditions, although generally it may be classified as a typical Mediterranean Continental climate of the Central Plateau.

[15] In the late 18th century, Bishop Juan Díaz de la Guerra changed the appearance of the fortress into that of an episcopal palace but during the War of Spanish Independence it was taken by the French who seriously damaged it.

[17] The Castle of Molina de Aragón is located on a hill commanding the surrounding valley, and is formed by an external line of walls with four gates and six towers of which four are currently in good condition.