Archaeological remains dating back to the Paleolithic, Neolithic, Bronze and Iron Ages have been found in Aranjuez, probably from hunting and farming settlers. Moreover, it is known from different documents that there has been a settlement here since Roman times.
In 1171 Alfonso VIII placed this frontier area under the domain of the Royal Order of Santiago. Aranjuez was definitively conquered in 1178 to become the residence of the Grand Masters of the Order, who spent long periods of retreat there, which would later take place at the Royal Palace, and consequently the Cross of Santiago (St. James Cross) forms part of the Aranjuez coat of arms.
King Alfonso VIII granted Oreja Castle to the Order of Santiago, in the name of its founder Rodrigo Fernández de Fuente Encalada.
In 1523 the Dehesa de Aranjuez became Royal property, since it was a part of King Carlos I’s estate and he converted it in a place for leisure and hunting. Felipe II named Aranjuez a Royal Site in 1560. It was decided to build a palace in Aranjuez in 1561 under the supervision of Juan Bautista de Toledo and the Royal Site was exclusively for use by the monarchs. The following monarchs continued Felipe II's work and designed Aranjuez to their tastes.
It was the Borbons who gave Aranjuez the boost to convert it in a place for courtiers. Feliple V was the first of the Borbons to settle there. The Royal Palace was extended, and the original Maestral Palace was demolished. Seven hundred families established in Aranjuez at the King’s service.
Fernando VI allowed free settlement by settlers. In 1747 development of the town began with contributions by Sabatini and Juan de Villanueva.
In 1984 it was declared an Historical Artistic Ensemble.
King Carlos III gave it a final boost with renovations and additions.
Carlos IV built fountains, the Labrador House, Chinescos, Casa de Marinos, Casa de Infantes, Godoy Palace and the Dukes of Medinaceli Palace. This brought an end to the golden age of the Royal Site because of the difficult situation Aranjuez was in due to poor administration and lack of profitability of the royal properties. This led to an unpopular reform of the Government's by-laws.
In 1801 the Treaty of Aranjuez was signed.
In 1808 the Aranjuez Mutiny took place.
In 1899 it was granted the status of Villa, and since then it is known as the Royal Site and Villa of Aranjuez.
In 2001 Aranjuez was listed a Cultural Landscape World Heritage Site by UNESCO.