The prevalence of differences and chaos inside the Seleucid empire paved the way for invading Syria and Palestine by the Roman general Pompey in 63 BC, when the Roman Empire was at the peak of its greatness, controlling almost all the Mediterranean coast, in addition to other vast areas.  More than half the population of Jerusalem at the beginning of the Roman period were Jews, while the rest were Arabs, Nabatean Arabs, Egyptians, and Phoenicians, according to the estimates of the Greek geographer Strabo around the 1st century AD.


The Romans delegated the task of governing Jerusalem and its vicinity to an Edomite dignitary called Herod the Great, also known as Herod the Edomite, in the year 40 BC, who conquered the city, with assistance from Rome three years after his appointment (in 37 BC).  He continued to rule Jerusalem, Palestine, and the surrounding territories until the year 4 BC, leaving behind great architectural achievements, and a distinguished style that carries his name until this day (the Herodian style).


Under Herod's rule, Jerusalem reached an unprecedented level of expansion, considered the largest in the city's history until then, including almost all of the Old City, with the exception of the Church of the Holy Sepulchre, and the area to the west, and reaching north to Bab Al-Amoud (Damascus Gate) area, expanding to the southwest until the borders of the Armenian Quarter.  On the southern side, it reached the Silwan Spring, but ended at the eastern wall, and there was no use for the remnants of the Dhour hill (the remains of the Jebusite city), which had been discarded.  Jerusalem assumed the network form in its planning, and started to look like a completely formed city.


The historical anecdote has it that Herod started to build two structures connected by gardens and water canals, one of which he called Ceasareum, in honor of his friend Octavius Augustus.  He also built a theater and an amphitheater, as well as a Hippodrome.  It is said that these Roman entertainment structures reflect the civilized image of Jerusalem which Herod rebuilt.

None of the huge public buildings constructed by Herod in the city remains in an integrated form, as a result of the total destruction wreaked by the Roman general Titus, son of the Emperor Vespasian in the year 70 BC, after suppressing the Jewish revolt which broke out towards the end of the 1st century AD against the Roman Empire.  Herod died in the year 4 BC, and his children divided the empire among them as Roman princes.  During the early years of their reign, Jesus Christ was born.


We do not see any noticeable developments in Jerusalem during the ensuing periods.  It seems that Herod's achievements took complete hold, and no strong ruler came after him, who was able to contribute to urban development.  Rulers started to be called "Procurators" and later on "Prefects".  Most of them reigned for short periods of time, whether those who were from the lineage of Herod, such as Herod Agrippa (ruled from 41 to 44 AD), and the rulers from Roman origins.


Between 52 and 60 AD, the conditions of Jerusalem and the surrounding area deteriorated and revolutions erupted. The Roman army, led by Titus, destroyed Jerusalem almost completely in 70 AD, and large parts of the city were totally leveled.  Sources state that Titus himself stayed in the city for months, overseeing its destruction.


The 10th Roman legion camped in Jerusalem to prevent any other revolutions in the city.  Most of its soldiers were Syrians and Arabs, and most of them settled in Jerusalem for 25 years, bringing their families to live with them, or married local women, and therefore became residents of the city.

When the Roman emperor Hadrian visited Jerusalem in 129 AD, he ordered that it be rebuilt as a Roman pagan settlement, and called it EeliusHadrianus, after himself.  The decision to rebuild the city was not simply a pure reconstruction undertaking, but was followed by a comprehensive urban Roman projection, including preventing the Jews from living in the city as of the year 135 AD.  The reconstruction process represented a demographic replacement in the true sense of the word.


The old walled city in its present form is originally a small Roman city, with very few changes.  Its main axes form a Roman continuity that was never interrupted.  This could be surmised from the main road which crosses the city from north to south, starting from Bab Al-Amoud (Damascus Gate) area in the north, from a huge semicircular colonnaded square, and continues south almost until the Zion Gate, and is named Cardo Maximus.  The other main road starts further down from Damascus Gate and bends east towards Al-Wad road, and continues south towards Silwan, parallel to the first road.  There are also many perpendicular roads (east to west), most important of which is the one that starts at the Lions Gate and extends to the west near the Austrian Hospice where it crosses the Cardo.  Another significant road starts at Jaffa Gate and extends east to Al-Haram Al-Sharif (Noble Sanctuary), referred to as the Decumanos.  This was also a central road, but not an important one as the other two.


Jerusalem was subject to the official religion of the Roman Empire, and there is sufficient evidence that the god Sirabis, the healing god of the Egyptians and Greeks was also worshipped, particularly around the holy waters of Bethesda pool, located in the courtyard of St. Anne Church (Al-Salahiyyah School).  It is also believed that the location where the Church of the Holy Sepulcher was built was also holy during the Roman times, and hosted a temple for the goddess Aphrodite, and a temple for the god Jupiter next to it, close to the point where the two perpendicular roads intersect.  Jerusalem was expanded to the west, adding the Church of the Holy Sepulcher and areas to the west of it.  It seems that Al-Haram Al-Sharif area housed two huge marble statues of Emperor Hadrian and Emperor Antonius.


Jerusalem remained without walls as long as the Roman army was camped in it, but after it withdrew towards the end of the third and beginning of the fourth centuries AD, Jerusalem's Roman walls were built as part of its defenses, as a small Roman garrison remained in the city.


Sources indicate that the city had a large number of Roman public buildings, including two government buildings, a theater, a large building with three corridors, a huge water fountain with four quadrants, a large building with twelve gates, a wide staircase, a public square, and others.  None of these buildings survived, however, and their exact locations cannot be identified.