Monzon is a small city in the autonomous community of Aragon, Spain. Its population was 17,176 as of 2014. It is in the northeast (specifically the Cinca Medio district of the province of Huesca) and adjoins the rivers Cinca and Sosa.

The first signs of constant human occupation in the area of Monzon come from Neolithic. There have been found some archaeological remains of that era on the deposits Sosiles Altos and Peña Lucas. Most vestiges of civilization come from the Bronze Age, where it is assumed that people settled in the area between the rivers Cinca, Sosa and clamor. The ilergetes were the people occupying these areas, who were defeated in the 3rd century BC, producing the Romanization of the area from the 2nd century BC. In the hills of the Ermita de la Alegria (the shrine of Joy) and the cells were found remains of Roman dwellings, being this area a key point in the connections from the cities of Caesaraugusta or Osca with Italy .

At the time of Muslim domination Monzon was disputed by the Banu Sabrit from Huesca and Banu Qasi from Zaragoza. It belonged to the Banu Hud in the 11th century and was taken by El Cid in 1083. The Christians were interested to conquer Monzon in order to cut communications between the Taifa kingdoms of Zaragoza and Lleida. The infant Pedro I reconquered Monzon in 1089 during the reign of his father Sancho Ramírez. Sancho Ramírez created the Kingdom of Monzón for the infant, future Pedro I, before he became king of Aragon. This situation lasted until 1126, when it reverted to Muslim hands for four years. Between 1130 and 1136 it was held by Christians, who lost the town in the period 1136-1141 to finally win her back.o 1143 happened to belong to the Templars.

The Cathedral de Santa Maria del Romeral (Saint Mary of the Rosemary Field), grew from the 9th century Torre del Homenaje which hosted kings and nobles. Here in 1109 Urraca of Castile married her second husband Alfonso I ("The Battler") despite the Church's objections concerning consanguinity.

During medieval times Monzon was a stronghold of the Knights Templar because of its strategic location between the Segre and Cinca valleys. It was also as an important center for joint legislative sessions for the various segments of Aragon, especially between the 13th and 17th centuries because of its location between Zaragoza and Barcelona.

During the 12th century Monzon was ruled by the infant Ramiro de Navarra, Tizon and Garcia Ramirez before his proclamation as King of Navarre among others. When in 1143 the Knights Templar assigns its rights to the Crown of Aragon receives in exchange the Castle of Monzon among others, where the main task of the Crown of Aragon happened. The most historically important event in this period is the enforced residence of James I ("The Conqueror") who spent part of his youth Monzon. After his father Peter II ("The Catholic") died in the Battle of Muret (1213); the Knights Templar in Monzon served as the young king's guardians and tutors. When the Pope Clement V extinguishes the Knights Templar, some parcels like Monzon resisted, and it was not until 1309 when it was conquested. In 1317 passes to sanjuanistas hands, although the hosts will lose its power gradually. Monzon also hosted numerous times the Cortes of the Crown of Aragon, between the 13th to 17th centuries. The Cathedral of Santa Maria del Romeral of Romanesque and the castle with its origins in the 9th century (Torre del Homenaje) welcomed the king and his nobles.

Places of interest include:

• El Castillo Templario (The Castle of the Knights Templar).
• La Catedral de Santa María del Romeral (The Cathedral of Saint Mary of the Rosemary Field, 12th and 13th centuries).
• El Convento de San Francisco (Saint Francis Convent, now dedicated to musical education and headquarters of the orchestral group Ensemble XXI).
• La Ermita de la Virgen de la Alegria (The Happiness Virgin Shrine, from the 17th century).
• Major House (16th and 17th centuries).
• La Puerta de Luzan (Luzan Gate)