All use of ousia was forbidden and it seemed as if Arianism had triumphed.

What you're describing is a standstill, not a victory (for either side).

the Arian Controversy, to an extent, was a dispute between the East and the West

Are you referring to Sabellius and Arius being polar opposites, with the former hailing from Libya (to the East of North Africa), and the other from Egypt (to the West of North Africa) ?

If you are simply referring to Rome and Constantinople, then bear in mind that the West was in multilateral decline, whilst the Orient was on the rise (no pun intended), and traditionalism is usually characteristic of rural, rather than urban, societies; which is also why Christianity initially spread in major cities, and the word for pagan originally meant villager. This is also the reason why all major heresies before the rise of the Carolingian Empire happened in the East, and Old Rome was well-regarded as a bastion of traditionalism and orthodoxy, whilst New Rome was constantly assailed by new and new heresies. Needless to say, the tables have turned in the second millennium, with the East as the new bastion of conservatism, and the (Wild?) West as the new Byzantium of heterodoxy.

Wedgeworth speaks of Orthodoxy as something that already existed when the Arian Controversy began.

Perhaps he is using the term retroactively, anachronistically, or proleptically ? If so, then there is no actual contradiction between him and Hanson.

Origen who has already rejected the term years before, and Paul of Samosata, who had been condemned for his use of h*m*-ousios, which the Church condemned as a Sabellian theology.

Origenism, adoptionism, and Sabellianism are about as (un)related as whales, flowers, and mosquitos: the former three are all heresies, the latter three are all living things, but, in both cases, one would have to cast a rather large or vaguely-defined net to encapsulate all three.

To the extent to which both Paul and Lucian, Arius' teacher, are both of Samosata, given the latter two's staunchly anti-Sabellian stance, the passage reads like a train wreck.

Sabellianism is the teaching that the Father, Son and Holy Spirit are three faces of one single Person.

The Latin persona, related to the Greek prosopon, comes from the Etruscan term for mask, metaphorically referring to one's various social roles or functions; thus, one relates as a parent to one's children, as a child to one's parents, as a servant to one's master, as a master to one's own servants, etc.

“the heretics typically took pre-existing Christian or Jewish tradition, combined it with certain philosophical rhetoric.”

That's like saying heretics talked; everybody did that, not just the heretics; Greek philosophy was the language of the day.

the controversy raged for no less than sixty years. It is highly unlikely that a controversy will last that long if the orthodox form was perfectly well known when it began.

Speaking of orthodoxy, picture Arius, the Egyptian (North-East African) priest, as an ultraorthodox; the heresy of the day was Sabellianism, a Libyan (North-West African) heresy, which was unanimously condemned throughout the entire empire, and everybody was taking a shot at it. Lucian of Samosata was the author of a strongly anti-Sabellian creed, vehemently condemning well-established or well-worn Sabellian expressions, such as h*m*ousios, or (second) light from (the first) light; as such, when Arius initially appeared on the scene, he seemed to many or most as simply proclaiming well-known truths; even as late as the first council, there were many that were certain that it was all either a big misunderstanding, or that his opponents were animated by ill-will and were intentionally portraying his (interpretable) words in a deeply perverted manner. According to Eusebius, when Athanasius took the stand during the council, he simply read passages from Arius' writings out loud, without too much (personal) commentary; at which point, Arius lost most of his supporters, because it became increasingly clear to the ecclesial gathering that his views simply weren't what they innocently and sincerely believed them to be.

when the controversy began, there were a general agreement in the church that the Son is subordinate to the Father

All sons are subordinate to their fathers; Arians interpreted this ontologically, rather than hypostatically. To provide a few modern examples:

• Feminists, for instance, argue that the traditional biblical interpretation of wives being obedient to their husbands is inherently misogynistic, relegating women to an inferior ontological status.
• In military terms, the one issuing the order is called superior, and the to whom it is given, inferior or subaltern; yet, they are both fellow soldiers.
• Similarly, racists, whether American or South-African, argue that masters are of necessity ontologically superior to their servants.

God is immutable and is only able to communicate with our world of change and decay through an intermediary

A belief common to Greek philosophers (such as Plato), Hellenistic Jews (such as Philo), and early Christians of all stripes, both orthodox (Justin Martyr and Tertullian) or heretical (Gnosticism and Arianism).

The intermediary is called demiurge, or logos, the latter term being notoriously borrowed by the fourth gospel.

Middle Platonist philosophy postulated a nous or Second Hypostasis as intermediary between the God and the physical world.

they found it effective to identify “the pre-existent Christ … with the nous or Second Hypostasis.”

the nous of Greek philosophy was “a second, created god lower than the High God”

No, the Platonic Nous is, to my knowledge, consistently identified, by both Hellenistic Jews and early Christians, with the One God and Father. The mind (nous) thinks (logos means thought), and eventually speaks out, in a loud voice, its inner thoughts (logos also means word). And God said, let there be light, etc.

the orthodoxy was that Christ is subordinate to the Father:

If so, then everybody except the Sabellians were orthodox.

The “conventional Trinitarian doctrine with which Christianity entered the fourth century … was to make the Son into a demi-god.”

If so, then Arianism is conventional Trinitarian doctrine; that it is Trinitarian, is no doubt; only the Sabellians weren't, and Arius was their greatest enemy; but I'm not sure if that's what he meant by conventional.

am I making a category error ?

The only error or imprecision I detected is that you fail or refuse to distinguish between (at least) two (different) types of subordination-ism: one Arian (ontological, heterodox or ultraorthodox), one Nicaean (hypostatical, moderate or orthodox).

Ultra-orthodoxy is no less prone to theological errors than hyper-corrections to grammatical ones.

Why would Hanson state that the pre-Nicene fathers believed that Christ is subordinate to the Father but still say there was no 'orthodoxy' on the subject of 'how divine is Jesus Christ?'

Because there was no unity on how to interpret the term; children are subordinate to their parents, animals are subordinate to their owners, tools to the craftsmen, etc.

Purpose

The fourth-century Arian Controversy began as a disagreement about who the Son of God is, relative to God. Later in the fourth century, the Holy Spirit was included in the debate. In the next (fifth) century, church councils made decisions about the nature of the Son after His incarnation. But the purpose of this article is to ask what the 'orthodox' view was when the Controversy began in the year 318, if there was any 'orthodox' view at the time.

Was Nicene Christology 'orthodox'?

For example, Steven Wedgeworth published an article in 2013 that speaks of Nicene theology as orthodoxy, implying that that theology already existed when the Arian Controversy began. For example, he refers to:

• “The orthodoxy of Athanasius,”
• “The orthodox bishops,”
• “The defeat of Orthodoxy” in the year 360 at the Homoean Synod of Constantinople,
• and Some defended “the orthodoxy” at the Western council at Arminium in 360.

He refers to anti-Nicens as 'heretics'.

In opposition to the 'orthodox', Wedgeworth referred to the ‘heretics’. He said, for example, that “the heretics typically took pre-existing Christian or Jewish tradition, combined it with certain philosophical rhetoric.” (See - Did Arius mix theology with pagan philosophy?)

He described anti-Nicene theology as supposedly 'orthodox'. For example, he refers to “supposed orthodox arguments (that) could perhaps be made against using 'substance' language in regards to the godhead.” In this regard, he mentions:

Origen, who have already rejected the term h*m*ousios a century before, and

The Church Council in the previous century that condemned the word h*m*ousios as Sabellian. That same council condemned Paul of Samatosota as a heretic. (Sabellianism is the teaching that the Father, Son, and Holy Spirit are three parts of the one God, however, in a different way than in Modalism.)

The term "supposed" in the phrase "supposed orthodox arguments" indicates that these arguments are not really 'orthodox'.

Conclusion

So, Wedgeworth seems to say that Nicene theology was the standard teaching with respect to Christ when the Controversy began.

Others say there was no orthodoxy.

Trevor Hart wrote an article in which he evaluated the book - The Search for the Christian Doctrine of God - by R.P.C. Hanson. Hart says that this book is the distillation of some twenty years of careful research and that nothing comparable in either scale or erudition exists in the English language. Hart wrote:

The main point Hanson wishes to make throughout the book is that what took place in the fourth century was not, as many accounts have suggested, a conflict between an ancient and established orthodoxy on the one hand and an emergent Christological heresy on the other.

For example:

What was 'orthodox' before the Controversy is heterodox today.

Much of what the Church Fathers taught "in the first three centuries … would have been forbidden as heterodox from 381AD onwards." For example, as already stated, a church council in the third century rejected the term h*m*ousios as Sabellian. And, as shown below, all of these church fathers described the Son as Subordinate to the Father.

In other words, what was 'orthodox' in the centuries before the Arian Controversy is regarded as heterodox today.

Arius was a Conservative. He did not create something new.

The view which Arius himself represented had long since co-existed alongside others within the church. While the church traditionally describes Arius as an innovator, scholarship now agrees that Arius was a conservative. His theology was not an emergent Christological heresy.

Nicene Christology was not 'orthodox' when the Controversy began.

Hanson described the word h*m*ousios and related words as "new terms borrowed from the pagan philosophy of the day" (RH, 846). For this reason, the claim is made that Nicene theology is an innovation. But Hart claims that the Nicene view was “one strand of the ancient interpretative tradition over against others, and not to be misconstrued, therefore, as a discovery, or as an essentially novel doctrinal departure.”

It would be important to understand who taught the h*m*ousian view before the Arian Controversy began. But the point is that Nicene Christology was not 'orthodox' when the Controversy began.

There were no clear boundaries.

When the controversy began, there were no “clearly defined groups and boundaries.” “Clear definition is just what was lacking, and was, in fact, what gradually came to be established as the century wore on.” Rowan Williams, in a 2001 book on Arius, agrees:

“Nicene apologists thus turn ‘Arianism' into a self-conscious sect - as if the boundaries of Catholic identity were firmly and clearly drawn in advance. But the whole history of Arius and of Arianism reminds us that this was not so.” (RW, 83)

Lewis Ayres, in his 2004 book, wrote similarly:

"Original Nicene theology was a fluid and diverse phenomenon, and one that kept evolving." Athanasius attempted to "offer a convincing version of that original Nicene theology" but "it was to be many years before those attempts evolved into what I shall term pro-Nicene theology." (LA, 99)

It was a search for orthodoxy; not a defense of orthodoxy.

For these reasons, Hanson "replaces the language of controversy ... with that of the metaphor of a search:

'This is not the story of a defence of orthodoxy, but of a search for orthodoxy' (RH, xix-xx).

Arius's dispute with his bishop prompted a search for the truth rather than a simple restatement of something which 'all Christians everywhere had always believed'.

"Orthodoxy on the subject of the Christian doctrine of God did not exist at first. The story is the story of how orthodoxy was reached, found, not of how it was maintained.” (RH, 870)

The orthodoxy was 'Subordinationism'.

There is a third option, namely that orthodoxy did exist when the controversy began, but it was not what we know today as orthodoxy. Specifically, there was a general agreement in the church that the Son is subordinate to the Father. Hanson explains as follows:

The Logos of Greek Philosophy

During the first three centuries, Greek philosophy was still a strong force in the Roman Empire. In that philosophy, God is immutable and is only able to communicate with our world of change and decay through an intermediary. For that reason, Middle Platonist philosophy postulated a nous or Second Hypostasis as an intermediary between the high God and the physical world. (Greek Philosophy)

The Apologists identified the Son as that Logos.

During those centuries, while Christians were still being persecuted by the Roman Empire, the Apologists (the pre-Nicene fathers) defended Christianity before the Gentile peoples of the Roman Empire. They found it effective to identify “the pre-existent Christ … with the nous or Second Hypostasis.” (Greek Philosophy)

Since the nous of Greek philosophy was “a second, created god lower than the High God” (Divine), the pre-Nicene fathers described Christ as “a subordinate though essential divine agent.” (Irenaeus) Therefore, as Hanson explains, going into the controversy, the orthodoxy was that Christ is subordinate to the Father:

The “conventional Trinitarian doctrine with which Christianity entered the fourth century … was to make the Son into a demi-god.” (Divine)

“Indeed, until Athanasius began writing, every single theologian, East and West, had postulated some form of Subordinationism. It could, about the year 300, have been described as a fixed part of catholic theology.” (RPC Hanson, “The Achievement of Orthodoxy in the Fourth Century AD” in Rowan Williams, ed., The Making of Orthodoxy (New York, NY: Cambridge Univ. Press, 1989) p. 153.)

“With the exception of Athanasius virtually every theologian, East and West, accepted some form of subordinationism at least up to the year 355.” (RH, xix) (RPC Hanson, The Search for the Christian Doctrine of God, Edinburgh: T & T Clark, 1988, p. xix.)

“Subordinationism might indeed, until the denouement (end) of the controversy, have been described as accepted orthodoxy” (RH, xix).

Theos had a wide range of meanings.

Theos is the Greek word that is translated as "god" or "God," depending on the context. Its Latin equivalent is Deus.

The pre-Nicene fathers did regard Christ as divine and described Him as theos, but as Hanson noted:

“The word theos or deus, for the first four centuries of the existence of Christianity had a wide variety of meanings. There were many different types and grades of deity in popular thought and religion and even in philosophical thought.” (theos)

In the thinking of the pre-Nicene fathers, “of course Christ was divine,” but since they assumed that many levels of divinity exist, the question that started the Arian Controversy was: “How divine, and what exactly did 'divine' mean in that context?” (theos)

Conclusions

A Complete Travesty

Hanson describes the conventional account of the Arian Controversy as a complete travesty. This current article discusses one aspect of that ‘travesty,’ namely that Nicene Theology already existed when the Arian Controversy began and that it was a struggle of an established orthodoxy against a newly developed heresy. Similar to Wedgeworth, many writers have assumed that:

“Arianism … had been from the outset an easily recognised heresy in contrast to a known and universally recognised orthodoxy.” (RH, 95) and that

Alexander and Athanasius maintained the ‘orthodoxy’ as we know it today.

As this article shows, and as Hanson states, this “is far from being the case” (RH, 95). Hanson wrote:

“At the outset nobody had a single clear answer to the question raised” (RH, 870).

“At the beginning of the controversy nobody knew the right answer. There was no 'orthodoxy' on the subject of 'how divine is Jesus Christ?', certainly not in the form which was later to be enshrined in the Creed of Constantinople.” (Beginning)

The orthodoxy as we know it today, did not yet exist. It was only created through that ‘search’ or ‘controversy’, particularly by the Cappadocian Fathers in the period AD 360-380.

Logos-theology was orthodox.

If there was an ‘orthodoxy’ when the Controversy began, it was the Logos-theology of the Apologists, in which the Son is a subordinate Intermediary between the High God and His creation:

“The great majority of the Eastern clergy (at Nicaea) ... were simply concerned with maintaining the traditional Logos-theology of the Greek-speaking Church.” (The Rise of Christianity by W.H.C. Frend)

You ask if you are making a category error with the three alternatives given in your question. The way to avoid a category error when asking about pre- and post-300 A.D. beliefs regarding the person of Christ is to state clearly what mainstream Christian belief was pre-300, then to state clearly what the post-300 beliefs of Arius were, then the clash will become evident. Therefore, this answer details those three steps.

1. Pre-300 A.D. mainstream Christian belief regarding the person of Christ

Irenaeus 130 - 200 - He was a Greek speaking Christian who had sat under Polycarp of Smyrna, who was himself a disciple of the Apostle John, and thus represents a link with the Church of the first century. Here is a quote about his beliefs regarding the person of Christ:

"Irenaeus' contribution to our understanding of the relationship of Christ to the godhead lies primarily in the things he rejected: Christ is not an emanation; the Logos did not emerge at a point in time. The Logos is neither an attribute nor an expression of God, who is an utterly simple essence and does not change. With these last assertions, Irenaeus sets a pattern for what has come to be called 'classical theology', the doctrine that God possesses certain incommunicable attributes (incapable of being shared by creatures), specifically, infinity, eternity, and immutability. Irenaeus offers a number of statements that sound rather like later, more fully developed trinitarian presentations: the Logos has always existed as the One who reveals the Father, and thereby is personally distinct from him, not a mode of the Father, to use later terminology. The Son is God by nature, true God.... He bequeathed to the Church this crucial sentence; Jesus Christus vere h*m*, vere deus, "Jesus Christ, true man and true God"." Heresies and Orthodoxy in the History of the Church, pp.83, 84 Harold O.J. Brown, Baker Book House 1998

Another early Church Father was Tertullian, 160 - 230. He was a layman who lived in Carthage in North Africa, and is the first notable representative of Latin-speaking Christianity. He was the first to put trinitarian theology into Latin. Whereas Irenaeus contributed breadth to the nascent theology of the Church, Tertullian gave it precision. Here are a few details of his teaching, accepted by the Church as orthodox:

"Tertullian expressed the idea the Jesus Christ possesses two natures, and in doing so laid the foundation for the formulation subsequently adopted at Chalcedon, but with respect to the concept, he is indebted to Irenaeus... Tertullian, like Irenaeus, insisted that what the Gospel tells us about the man Jesus must also be said of the Son as God... Tertullian's language anticipates the explicit statements of Chalcedon. It reveals that what we shall come to know as Chalcedonian orthodoxy was born is God, and also, incidentally, that we may speak of God, in the person of the Son was already in evidence at least by implication as early as the beginning of the third century." (Ibid. pp.78, 84, 85)

2. Post-300 A.D. beliefs of Arius regarding the person of Christ

Arius was born in Libya circa 260, and died in 336. He became a senior presbyter in Alexandria in 311. It was in 318 that he clashed with Bishop Alexander, his ideas being parallel and contrasting with Origen's teaching, and owing much to secular Greek concepts of God. Thus, his preaching appealed to a lot of pagans at that time.

Briefly, Arius taught that only the Father is God in the fullest sense; the Son and the Spirit are ontologically inferior (which means that Arianism is also called 'Subordinationism'.) From another book is this explanation:

"[Arius] took a step beyond Origen, denying the essential unity of the Son with the Father. Arianism taught that there was a time when the Son did not exist. It was chiefly this heresy that the early creeds targeted when they affirmed that the Son is consubstantial - that is, of the same essence (Greek, ousia) or substance (Latin, substantia) with the Father (and the Spirit). Thus, according to Arians, the Son is God's first creation, through whom he then created the world. As the label suggest, Semi-Arianism (quite close to Subordinationism) proposes a middle way between Arianism and orthodoxy: although the Son is not of the same essence (h*m*ousios), he is of a similar essence (h*m*iousios). It has been said that at this point in history the difference between Christianity and another religion depended solely on a vowel." Pilgrim Theology, p.178, Michael Horton, Zondervan 2011

3. The clash requiring Arius's teachings to be declared apostate by mainstream Christianity

Given that during the century before Arius, the Christian Church already believed in "Jesus Christ, true man and true God", the clash with what Arius taught centered on whether the Logos / Word / Son of God had been created by God the Father, or not. A mantra of Arius was, "There was when the Son was not". But here is the irony - Origen never tired of emphasizing that the Logos / Word is God's very Son and in no way created or begotten in time, yet Arius claimed Origen as the source of his subordinationism of the Son!

All the clutter having been cleared away, we can see how matters stood a century before Arius clashed with the Church in 318, and why what he taught inevitably created this clash. The orthodox view of Christ (in relation to God) has been exemplified by such early Church Fathers as Irenaeus and Tertullian (there were more, of course). The view of Origen's Subordinationism has been shown to clash with Arius's view of Subordinationism. As for the views of Wedgeworth and Hanson, they should be compared with the views of those pre-4th Century Church Fathers, for those who have the time and inclination to do that.

First of all I'd like to apologize that I'm not an expert so my answer may not be correct.

What was the 'orthodox' view of God and Christ when the Arian Controversy began?

The counterquestion is: What exactly does "orthodox" mean?

From my understanding, it means that somebody is believing in what the official doctrine of some religion is saying.

Around the year 300, there was no "official" doctrine (such as the Catechism today). And if there really were an agreement among Christians at that time, there would not have been so many Arians. So we also cannot say that whatever was the agreement can be seen as "official doctrine".

So Hanson's point of view makes sense.

Did he use the term 'orthodoxy' proleptically ...

Definitely yes.

This is more or less the "official" way used by the Catholic Church when judging a person that was living in the past.

Why would Hanson state ... subordinate ... but still say ...

Because the word "subordinate" is not very specific:

It would both describe Arianism and the Orthodox Church'es idea of the Tinity - and everything in between.