Roman Catholics and the Orthodox Church venerate or give devotion to Mary, but is there any evidence of this within the Early Church Fathers or is this nothing more than a later development?
Is there any evidence to the devotion of Mary in the early church?
The short answer seems to be yes.
The oldest known prayer to Mary is the Sub Tuum Praesidium which dates to the 3rd (or 4th) century A. D.
The Sub tuum praesidium is probably the oldest Christian prayer dedicated to the Blessed Virgin Mary. This prayer was long used in both Eastern and Western rites, even if numerous variants existed at the time. In 1917, the John Rylands Library in Manchester managed to acquire a large panel of Egyptian papyrus -- the exact area where they were discovered is unknown -- including an 18 cm by 9.4 cm fragment containing the text of this prayer in Greek.
I. An Egyptian Papyrus of the Third Century
C.H. Roberts published this document in 1938 (cf. Catalogue of the Greek and Latin Papyri in the John Rylands Library, III, Theological and literacy Texts, Manchester 1938, pp. 46-47). Roberts then dated this piece of papyrus back to the fourth century, thinking it was impossible to find an invocation to the Theotokos before this century (we will however see below, that the expression Theotokos was already in use in Alexandria before 250).
However his colleague E. Lobel, with whom he collaborated in editing the Oxyrhynchus papyri, basing his arguments on pure paleographic analysis, argued that the text could not possibly be older than the third century, and most probably was written between 250 and 280. A contributor to Roberts, H.J. Bell, even said that this document might be a "model for an engraver" considering the beauty of the uncials. The Sub tuum praesidium thus precedes by several centuries the Ave Maria in Christian prayer.
On the papyrus, we can read:
.ΠΟ ΕΥCΠΑ ΚΑΤΑΦΕ ΘΕΟΤΟΚΕΤ ΙΚΕCΙΑCΜΗΠΑ ΕΙΔΗCΕΜΠΕΡΙCTAC AΛΛΕΚΚΙΝΔΥΝΟΥ ...ΡΥCΑΙΗΜΑC MONH ...HEΥΛΟΓ
And an English translation could be: Under your mercy we take refuge, Mother of God! Our prayers, do not despise in necessities, but from the danger deliver us, only pure, only blessed.
II. A Prayer of Great Value
Like all ancient liturgical prayers, the Sub tuum praesidium has a noble simplicity and conciseness of expression, combined with a fresh spontaneity.
Several biblical references may be seen, the last term, "blessed", referring to Elizabeth's salutation: Benedicta tu in mulieribus - Blessed art thou among women (Luke I, 42).
The supplication to the Virgin Mary by the Christian community in danger places, without doubt, the invocation in the context of persecution (of Valerian or of Decius).
A first remarkable point resides in the fact that the Egyptian Christian community turns directly to Mary and asks for her protection. Christians have realized that the Virgin is close to their suffering and asked her help explicitly, thereby recognizing the power of her intercession.
There seems to be little archeological evidence of any devotion of the Virgin Mary in the Early Church catacombs. But at the same token there may be glimmers of a Marian devotion amongst the faithful of the first few centuries after the Crucifixion of Our Lord Jesus Christ.
There are many Christian images concealed within the Catacombs of Priscilla, in Rome. One of these images is the first known image of the Virgin Mary, painted around the time of Christian persecution in 170 BC. The image of Mary nursing Jesus painted as a fresco high upon the walls of the catacomb was meant to refresh the persecuted Christian’s spirits and give them hope as Mary’s gentle gaze encourages them. Upon examining the fresco we begin to observe the intricate symbolic details that are included. For example, the clothing worn by the women within the painting reveals to us that the woman is in fact Mary the mother of Jesus. She is shown wearing a woolen garment which was most commonly worn by Roman matrons and is also wearing a short veil that was worn by dedicated virgins. We then recognize the baby on her lap as Jesus, who is glancing over his shoulder to observe another figure painted to the left. This figure is a man who is pointing up to the star of Bethlehem, he is dressed in a cloak that signifies him as a philosopher of distinction, but there is debate on who this figure was specifically. Some claim that it is depicting the prophet Isaiah who predicted that “The Lord Himself shall give you a sign. Behold a Virgin shall conceive and bear a son, and his name shall be called Emmanuel”, but others claim that the man is representing the prophet Balaam who said “a star shall come forth out of Jacob, and a scepter shall rise out of Israel”. Reaching out over the prophet and Mary is a blossoming tree branch that refers to the Old Testament prophecy “The Rock of Jesse has blossomed; the Virgin has brought forth Love and Man”. - First Known Image of Mary, In Catacombs of Priscilla
This is the oldest known image of the Virgin Mary (seen apparently nursing the infant Jesus on her lap). It is located in the Catacomb of Priscilla on the Via Salaria in Rome. It is dated circa A.D. 150. - Foundations of Marian Devotion in the Early Church
Wikipedia has this to say about the subject:
Early veneration of Mary is documented in the Catacombs of Rome. In the catacombs paintings show the Blessed Virgin with her son. More unusual and indicating the burial ground of Saint Peter, was the fact that excavations in the crypt of Saint Peter discovered a very early fresco of Mary together with Saint Peter. The Roman Priscilla catacombs contain the known oldest Marian paintings, dating from the middle of the second century. In one, Mary is shown with the infant Jesus on her lap. The Priscilla catacomb also includes the oldest known fresco of the Annunciation, dating to the 4th century. - Marian art in the Catholic Church
Some of the Early Church Father wrote about the perpetual virginity of Mary.
In the year AD 383, Jerome writes that Ignatius, Polycarp, Justin Martyr, and Irenaeus all “held these same views” of Mary’s perpetual virginity and “wrote volumes replete with wisdom” (in his The Perpetual Virginity of Blessed Mary: Against Helvidius, section 19). No writings from these 4 men survived that unambiguously identifies their belief in this doctrine, but we assume Jerome had access to some of their many works that did not survive until the modern day.
But the pious confession of the believer is that, with a view to our salvation, and in order to connect the universe with unchangeableness, the Creator of all things incorporated with Himself a rational soul and a sensible body from the all-holy Mary, ever-virgin, by an undefiled conception, without conversion, and was made man in nature (Against Beron & Helix, Fragment VIII)
Origen acknowledges the view and the reasonable nature of its proponents, without fully endorsing it:
For if Mary, as those declare who with sound mind extol her, had no other son but Jesus (Commentary on John 1:6)
They thought, then, that He was the son of Joseph and Mary. But some say, basing it on a tradition in the Gospel according to Peter, as it is entitled, or The Book of James, that the brethren of Jesus were sons of Joseph by a former wife, whom he married before Mary. Now those who say so wish to preserve the honour of Mary in virginity to the end (Commentary on Matthew 10:17)
Origen circa 200 A. D. was one of the first in the church to "venerate” Mary as she subsequently came to be honoured as the ever-virgin.
And they [the townspeople] spoke, wondering, (not knowing that He was the son of a virgin, or not believing it even if it was told to them, but supposing that He was the son of Joseph the carpenter,) “is not this the carpenter’s son?” And depreciating the whole of what appeared to be His nearest kindred, they said, “Is not His mother called Mary? And His brethren, James and Joseph and Simon and Judas? And His sisters, are they not all with us?” They thought, then, that He was the son of Joseph and Mary. But some say, basing it on a tradition in the Gospel according to Peter, as it is entitled, or “The Book of James,” that the brethren of Jesus were sons of Joseph by a former wife, whom he married before Mary. Now those who say so wish to preserve the honour of Mary in virginity to the end, so that that body of hers which was appointed to minister to the Word which said, “The Holy Ghost shall come upon thee, and the power of the Most High shall overshadow thee,” might not know intercourse with a man after that the Holy Ghost came into her and the power from on high overshadowed her.And I think it in harmony with reason that Jesus was the first-fruit among men of the purity which consists in chastity, and Mary among women; for it were not pious to ascribe to any other than to her the first-fruit of virginity. Origen on Matthew
Some 25 years before Origen's influence was Irenaeus who did indeed teach that Mary was the "new Eve". He also taught the Jesus was the "new Adam".
In accordance with this design, Mary the Virgin is found obedient, saying, “Behold the handmaid of the Lord; be it unto me according to thy word.”3747 But Eve was disobedient; for she did not obey when as yet she was a virgin. And even as she, having indeed a husband, Adam, but being nevertheless as yet a virgin (for in Paradise “they were both naked, and were not ashamed,” inasmuch as they, having been created a short time previously, had no understanding of the procreation of children: for it was necessary that they should first come to adult age, and then multiply from that time onward), having become disobedient, was made the cause of death, both to herself and to the entire human race; so also did Mary, having a man betrothed [to her], and being nevertheless a virgin, by yielding obedience, become the cause of salvation, both to herself and the whole human race.... For what the virgin Eve had bound fast through unbelief, this did the virgin Mary set free through faith. Against Heresies Book III Chapter XXII
Images of the Blessed Virgin appear in the catacombes; see the works by archeologist Josef Wilpert (1857-1944).
Also, the cult of St. Thecla (follower of St. Paul) was almost as big as that for the Blessed Virgin in the early Church.