So, I think it very much depends on the variety of monotheism we're talking about here, as they are not all identical (i.e. we don't all adhere to a doctrine as radical as Islamic
Tawhid (oneness of God) and
Shirk (assigning no partners to Allah) with unqualified rejection of all intermediaries).
In my own faith tradition, as you can tell from the aforementioned, the "
gods" of the pre-Christian era were not denied in their actual existence (generally speaking) when the one God of the Bible was proclaimed by the early church as the only Creator and Self-existent Supreme Being, the sole recipient of worshipful adoration.
On the contrary, these supernatural beings from the traditional cults were understood anew as either angels or demons and the 'pantheon' remained in place, with the one major qualification being that one could no longer worship any lesser divinities. But if they were beneficent ones reconceived as holy angels or their attributes / qualities transposed to the cult of deceased saints, then you could still continue to venerate them, invoke their names for intercession before the Most High and practise a whole range of devotions.
It wasn't hard to transfer them into this 'angelic' realm as pre-existent, celestial beings before the divine presence. As St. Basil described it:
"
The birth of the world was preceded by a condition of things suitable for the exercise of supernatural powers, outstripping the limits of time, eternal and infinite. The Creator and Demiurge of the universe perfected His works in it, spiritual light for the happiness of all who love the Lord, intellectual and invisible natures, all the orderly arrangement of pure intelligences who are beyond the reach of our mind and of whom we cannot even discover the names. They fill the essence of this invisible world, as Paul teaches us. For 'by him were all things created that are in heaven, and that are in earth, visible and invisible whether they be thrones or dominions or principalities or powers' Colossians 1:16 or virtues or hosts of angels or the dignities of archangels."
(
St. Basil of Caesarea [330 – 379] Hexaemeron, Homily 1.5)
The Fathers followed the rendering of
Deuteronomy 32:8, evident in the earliest Qumran fragment (the manuscript evidence supports the conclusion that this is the original text), which refers to the
elohim, the gods (אלהים) of the nations, as the בני אלהים, 'sons of God': "
When the Most High divided the nations and distributed the children of Adam abroad, then He established the bounds of the nations according to the number of the sons of God" (
Deut. 32:8) and took this very literally, as you can see from this excerpt from the writings of the third century church father Origen (184 - 253 CE):
CHURCH FATHERS: Contra Celsum, Book V (Origen) (newadvent.org)
"It appears to me, indeed, that Celsus has misunderstood some of the deeper reasons relating to the arrangement of terrestrial affairs, some of which are touched upon even in Grecian history, [concerning] certain of those who are considered to be gods...
And the learned among the Egyptians can enumerate innumerable instances of this kind, although I do not know whether they include the Jews and their country in this division.
And now, so far as testimonies outside the word of God bearing on this point are concerned, enough have been adduced for the present. We say, moreover, that our prophet of God and His genuine servant Moses, in his song in the book of Deuteronomy, makes a statement regarding the portioning out of the earth in the following terms: 'When the Most High divided the nations, when He dispersed the sons of Adam, He set the bounds of the people according to the number of the angels of God; and the portion was His people Jacob, and Israel the cord of His inheritance'...
And they were conducted by those angels, who imprinted on each his native language, to the different parts of the earth according to their deserts."
With that scriptural exegesis, the early Christians had no problem 'inculturating' and baptizing elements of the pagan heritage after conversion, for as St. Clement of Alexandria noted they were considered by the new monotheist faith to have been worshipping the one true God already, just in an imperfect manner through his emissaries in the natural world - the beings He had set over the human affairs as guardians:
CHURCH FATHERS: The Stromata (Clement of Alexandria) (newadvent.org)
"And that the men of highest repute among the Greeks knew God, not by positive knowledge, but by indirect expression, Peter says in the Preaching: "Know then that there is one God, who made the beginning of all things, and holds the power of the end; and is the Invisible, who sees all things; incapable of being contained, who contains all things; needing nothing, whom all things need, and by whom they are; incomprehensible, everlasting, unmade, who made all things by the 'Word of His power".
Then he adds: Worship this God not as the Greeks, — signifying plainly, that the excellent among the Greeks worshipped the same God as we, but that they had not learned by perfect knowledge that which was delivered by the Son. Do not then worship, he did not say, the God whom the Greeks worship, but as the Greeks, — changing the manner of the worship of God, not announcing another God...
[God] made a new covenant with us; for what belonged to the Greeks and Jews is old. But we, who worship Him in a new way, in the third form, are Christians. For clearly, as I think, he showed that the one and only God was known by the Greeks in a Gentile way, by the Jews Judaically, and in a new and spiritual way by us."
While many of the cultic practices directed towards the gods were, indeed, suppressed in the Christian period (
i.e. blood sacrifices, Vestal Virgins with the sacred flame etc.), others were simply 'christened' and subsumed within the growing veneration of the Saints and Angels - of which their quickly became a canonized saint or guardian angel in heaven with a church-approved local or universal cult and patronage over literally
every dimension of human life and the natural world, which their pagan forbears could have assigned to, or personified as, a god or goddess.
From St. Vitus the patron saint of comedians, St. Isidore the saint of farming and St. Genevieve the saint of drought, to St. Patrick the patron saint for those afraid of snakes and St. Francis the patron saint for animals and St. Valentine the patron saint of lovers, all bases were covered.
And that's before one gets to the 'celestial realm' and the order of invisible angels.
In this respect, the shift to monotheism was arguably less that of a '
theo-democracy to a theo-totalitarianism', because the local traditions, cults and '
division of power to specialists', which could be invoked for their intercession whenever the need arose in your life for their technical assistance, persisted and even thrived under the new 'Divine Leadership'.
At the level of popular piety, there was continuity as well as rupture - as in most "
revolutions". Thus, the early 20th century Russian Orthodox scholar Sergius Bulgakov could write:
"Paganism, in its elemental clairvoyance, knew the heavenly foundation of the universe, but equated the angelic hierarchies with gods, or more precisely, the gods, “sons of God” (Job 1:6; 2:1), with the very God. The Christian sense and truth of Platonism is disclosed only in angelology as the doctrine about heaven and earth in their interrelations"
(Sergius Bulgakov, Jacob’s Ladder, 83)
I broadly agree with Harel's premise.
