Marked by all the episodes which lead to the origin of the Portuguese Nation, the Guimarães Castle also assisted to the birth of the first king of Portugal, D. Afonso Henriques.
The first military structure built in Vimaranes (the previous toponym of Guimarães) dates probably from the 10th century, built by order of Mumadona Dias who inherited from her husband the lands of Portucale. This structure was supposed to house the population in case of attack and the defence of the Monastery also ordered by D. Mumadona.
These lands are donated, around the year 1100, by king Adonso VI of Leon to D. Henrique of Bourgogne, forming the Portucalense County.
Count D. Henrique and his wife, D. Teresa of Leon, installed in Vimaranes, and supposedly built a new Castle, reinforced the Donjon and improved all the defensive structures, making of this their residence.
In this Castle, possibly, was born the first Portuguese king, D. Afonso Henriques, and in it he resisted, already on his fight for freedom, to the attack of the king Afonso VII of Leon forces, in 1127, and in the S. Mamede field, on the fortress surroundings, he defeated on the next year, his mother’s D. Teresa army.
The Castle kept its importance throughout the centuries of disputes between Portugal and Castille.
Already during the reign of king D. João I, in 1389, after another confront with Castille, several works for reinforcement of the defensive structure take place, and the town got its toponym of Guimarães.
With the military progress, the walls and the castle loose their significance and in the 16th century, the Guimarães Castle was working as a prison.
During the reign of D. Luís, in 1881, the Castle is classified as a first class Historical Monument.
Nowadays it is classified as a National Monument.