The city of Montemor-o-Novo, seat of the Municipality, village of a most remote origin, was initially placed inside the wall of the Castle, spreading atterwards to the northern slope where it is presently set.
The municipality received charters from the kings D. Sancho I (1203) and D. Manuel (1503) and had an important role in the fight against the Castilian occupation (1580 1640) and during the French invasions (in the beginning of the 19th century).
The apogee of Montemor-o-Novo were the 15th and 16th centuries, when the prosperity brought by commerce allied itself with the fact that the court stood for large periods in Évora, which often made the town a stage to some important political events with the Courts and the king's permanence in the Palace of the Alcaides.
In Montemor, in 1496, D. Manuel has made the historical decision to demand the discovery of the seaway to India, during the general councils that took place in the city.
In the numbering ordered by D.João III in 1527, the first census to the population in Portugal, 899 houses were counted, the 6th place among the populations of the Alentejo. King Sebastião gave it, in 1563, the title of Notable Town, considering it was an ancient place with a large population, surrounded and enriched with churches, temples, monasteries and much more noble buildings and houses.
Some of the most important architecture works existing in the city date back from those times, as the Misericórdia , the Saudação, St. Francisco and St. António Convents, the Chapel of Nossa Senhora da Visitação, The Old Hospital and the portal of St. Maria do Bispo.
Concerning history some events became visible over the quiet population's daily life. Among them we must refer the resistance to the first French invasion, commanded by Junot in 1808, near the bridge of Lisbon; the loitering in 1834, of the major state of the Army commanded by Saldanha during the civil fights between liberals and miguelistas and D. Maria and D. Fernando's visit in 1843. Montemor-o-Novo played a most active role in the resistance to the fascist dictatorship and in the fight for better life conditions and freedom.
With the 25 of April, Montemor-o-Novo was in the first line in the conquest of the revolution, namely in the implantation of the Democratic Local Power and Land Reform. Another important element in the recent history of Montemor-o-Novo it's the fact that it became a city by decision of the Assembly of the Republic in the 11th of March, 1988.