Archaeological findings, although limited, demonstrate the Roman presence in the town and its surroundings: coins, a cameo, a stele of limestone and a brake horse dated in the 2nd century.

Neighbours Francisco Morales and María Pérez discovered the Treasure of Guarrazar by chance; it is the most important of those found in the Peninsula on the Visigoth era.

The most valuable of all is the crown of king Recesvinto (which today names the main square of the town): blue sapphire parts come from the former Ceylon, now Sri Lanka.

There were also many fragments of sculptures and the remains of a building, perhaps a Roman delubrum (sanctuary or place of purification); in the following centuries it was dedicated to Christian worship as a church or oratory, which housed a number of graves: in the most important was found a skeleton lying on a bed of lime and sand, and preserved the stone slate, whose Latin inscription mentions a priest named Crispín, dating from 693 (51st year of the reign of Égica, year of the 16th Council of Toledo.

Initiated recruitment in times of Alfonso VII, Guadamur appears as the village council of Toledo, who pay taxes and which jurisdiction depends.

There is documentation which provides proof of the existence of traditional private property of citizens from Toledo around Guadamur and this can be traced to the reign taifa by the Arabic names of the farms.

During the 13th, 14th and 15th centuries, this land was in a progression towards the noble scheme, and it begins to feel the shame of servitude in a monarchical decomposition, strengthened nobility, peasant resistance, religious conflict, plague and livelihood crisis.

Guadamur entered medieval history under the hand of Pedro López Ayala, son of the royal chancellor and mayor of Toledo, whose family disputes control to the Silva.

The son of Don Pedro was the first Count of Fuensalida (1470); two years before he had obtained permission from the king to build a castle in Guadamur, probably on a previous moose Arabic watchtower.

In these years is also built a pillory on the square of the village, insignia of jurisdiction and execution, which replaced the old gallows of wood (still a hill not far from the castle retains the name of "Cerro de la Horca").

The III Count of Fuensalida (1489–1537) hosted Prince Don Felipe and Doña Juana in Guadamur on 11 July 1502, just after they had been appointed heir and heiress to the Crown of the Kingdom of Castile.

According to documents from 1811, the village contributes towards supplying the infantry and artillery troops quartered in Mazarambroz with daily rations of bread, meat, wine, pulses, salt, oil, coal, wood, barley straw and bran.

In 1887 the town sold the castle to the sixth count of Asalto, a distant relative of Ayala, who inherits from his son, the Marquis de Argüeso, Member of Parliament for Tarragona.

In the late 19th century, being mayor Lorenzo Navas, former colonial governor of Tarlac (Philippines), the old well of the council is replaced by a four-pipe now defunct (in Recesvinto Square) and a trough-pillar that gave name to the Plaza del Pilar.

At this time Guadamur presents an example of integral collectivism: only two farms occupied by then 52.2% of the municipality, and after the military uprising was the seizure of these and others, as well as small shops and homes of considered enemies of the Republic.

On 25 August 1936 the community "Pablo Iglesias" was established, the entire municipality being integrated into it, breaking the boundaries of private property and dividing the land into plots.

On 7 May 1937 the Nationalist army broke the front to the south of the city of Toledo and penetrates to the north of the municipality of Guadamur; in such action captured the neighbouring population of Argés, recovered by Republican forces a few days later.

In October 1937 the district was integrated gradually losing its originality, as in many other places, under pressure from its communist partners, who advocated a cooperative basis to small farmers, industry and services arising from the fragmentation.

As regards to the repression carried out by Francoist Spain, apart from the 26 fatalities recorded natural Guadamur, many residents went to the new state prison and suffered humiliation, exile, banishment and condemnation to death, sometimes switched with the customary charge of "assisting the rebellion."