In his, (Link to: Dialogue with Trypho), Justin wrote;
-  The Word is Not as an Inanimate Power
-  The Word is a Person. 
-  The Word is Begotten of the Father's Substance.
-  He (Jesus) was God, 
-  He (Jesus) was Son of the only, unbegotten, unutterable God. 
-  He (Jesus) was God, indivisible from the Father. 
-  He (Jesus) was God, inseparable from the Father. 
-  (Jesus) was Begotten from the Father but not by abscission [cutting off][/size]
The First Apology of Justin, (150 AD) (175 years before Nicea)  "But our Physician is the only true God, the unbegotten and unapproachable, the Lord of all, the Father and Begetter of the only begotten Son. 
 We have also as a Physician the Lord our God, Jesus the Christ, the only begotten Son and Word, before time began, but who afterwards became also man, of Mary the virgin. For "the Word was made flesh." 
 Being incorporeal, He was in the body; being impassible, He was in a passible body; being immortal, He was in a mortal body; being life, He became subject to corruption, that He might free our souls from death and corruption, and heal them, and might restore them to health, when they were diseased with ungodliness and wicked lusts. 
We will prove that we worship him reasonably; for we have learned that he is the Son of the true God Himself, that he holds a second place, and the Spirit of prophecy a third. For this they accuse us of madness, saying that we attribute to a crucified man a place second to the unchangeable and eternal God, the Creator of all things; but they are ignorant of the Mystery which lies therein" 
Chapter XXXVI Who is this King of glory? 'And 
the Holy Spirit, either from 
the person of His Father, or from 
His own person, answers them, `The Lord of hosts, He is this King of glory.'
The Epistle Of Ignatius To The Philippians Chap. II.  Unity Of The Three Divine Persons. [100 AD, 225 years before Nicaea] 
There is then one God and Father, and not two or three; One who is; and there is no other besides Him, the only true [God]. For "the Lord thy God," saith [the Scripture], "is one Lord."(9) And again, "Hath not one God created us? Have we not all one Father?(10) And there is also one Son, God the Word. For "the only-begotten Son," saith [the Scripture], "who is in the bosom of the Father."(11) And again, "One Lord Jesus Christ."(12) And in another place, "What is His name, or what His Son's name, that we may know?"(13) And there is also one Paraclete.(14) For "there is also," saith [the Scripture], "one Spirit,"(15) since "we have been called in one hope of our calling."(16) And again, "We have drunk of one Spirit,"(15) with what follows. And it is manifest that all these gifts [possessed by believers] "worketh one and the self-same Spirit."(17) 
There are not then either three Fathers,(18) or three Sons, or three Paracletes, but one Father, and one Son, and one Paraclete. Wherefore also the Lord, when He sent forth the apostles to make disciples of all nations, commanded them to "baptize in the name of the Father, and of the Son, and of the Holy Ghost,"(19) not unto one [person] having three names, nor into three [persons] who became incarnate, but into three possessed of equal honour.
Athenagoras the Athenian  A Plea For the Christians Philosopher and Christian   [177 AD] (148 years before Nicea)
while men who reckon the present life of very small worth indeed, and who are conducted to the future life by this one thing alone, that 
 they know God and His Logos, what is the oneness of the Son with the Father, what the communion of the Father with the Son, what is the Spirit, what is the unity of these three, the Spirit, the Son, the Father, and their distinction in unity; and who know that the life for which we look is far better than can be described in words, provided we arrive at it pure from all wrong-doing; who, moreover, carry our benevolence to such an extent, that we not only love our friends ("for if ye love them," He says, "that love you, and lend to them that lend to you, what reward will ye have? ",-shall we, I say, when such is our character, and when we live such a life as this, that we may escape condemnation at last, not be accounted pious?
FatAthenPleaChr
 180 AD (145 years before Nicea) Theophilus of Antioch
Chapter XV. - Of the Fourth Day. " In like manner also the three days which were before the luminaries, are 
types of the Trinity,. of God, and His Word, and His wisdom." And the fourth is the type of man, who needs light, that so there may be God, the Word, wisdom, man. Wherefore also on the fourth day the lights were made. 
Chapter XV. - Of the Fourth Day, To Autolycus 2:15) 
Clement Of Alexandria Stromata, Book V, ch. 14  190 AD (135 years before Nicea) "
I understand nothing else than the Holy Trinity to be meant; for the third is the Holy Spirit, and the Son is the second, by whom all things were made according to the will of the Father." (Stromata, Book V, ch. 14)
 
"When [John] says: 'What was from the beginning [1 John 1:1],' 
he touches upon the generation without beginning of the Son, who is co-equal with the Father. 'Was,' therefore, is indicative of an eternity without a beginning, just as the Word Himself, that is the Son, being one with the Father in regard to equality of substance, is eternal and uncreated. That the word always existed is signified by the saying: 'In the beginning was the Word' [John 1:1]." (fragment in Eusebius History, Bk 6 Ch 14; Jurgens, p. 188)
 
 'For both are one  that is, God. For He has said, "In the beginning the Word was in God, and the Word was God." (The Instructor, Book 1, ch 8) 
"Despised as to appearance but in reality adored, [Jesus is] the Expiator, the Savior, the Soother, 
the Divine Word, he that is quite evidently true God, he that is put on a level with the Lord of the universe because he was his Son." (Exhortation to the Greeks, 10:110:1). 
Gregory the Wonderworker (Declaration of Faith  [A.D. 265]). (60 years before Nicea) 
"There is one God . . . 
There is a perfect Trinity, in glory and eternity and sovereignty, neither divided nor estranged. Wherefore there is nothing either created or in servitude in the Trinity; nor anything superinduced, as if at some former period it was non-existent, and at some later period it was introduced. And 
thus neither was the Son ever wanting to the Father, nor the Spirit to the Son; but without variation and without change, the same Trinity abides ever" 
 200 AD Tertullian   (125 years before Nicea)"
[God speaks in the plural Let us make man in our image] because already there was attached to Him his Son, a second person, his own Word, and a third, the Spirit in the Word....one substance in three coherent persons. He was at once the Father, the Son, and the Spirit." (Against Praxeas, ch 12) 
"Thus the connection of 
the Father in the Son, and of the Son in the Paraclete, produces three coherent Persons, who are yet distinct One from Another. These Three are, one essence, not one Person, as it is said, 'I and my Father are One' [John 10:30], in respect of unity of Being not singularity of number" (Against Praxeas, 25) 
"As if in this way also one were not All, in that All are of One, by unity (that is) of substance; while the mystery of the dispensation is still guarded, which distributes 
the Unity into a Trinity, placing in their order the three Persons  the Father, the Son, and the Holy Ghost: three, however, not in condition, but in degree; not in substance, but in form; not in power, but in aspect; yet of one substance, and of one condition, and of one power, inasmuch as He is one God, from whom these degrees and forms and aspects are reckoned, under the name of the Father, and of the Son, and of the Holy Ghost." (Against Praxeas, by 
Irenaeus Against Heresies  [a.d. 120-202.] [125 years before Nicaea] disciple of Polycarp a disciple of  John 
BOOK IV.Thus also did Rahab the harlot, while condemning herself, inasmuch as she was a Gentile, guilty of all sins, nevertheless receive 
the three spies,(8) who were spying out all the land, and hid them at her home; [which three were] doubtless [a type of] the Father and the Son, together with the Holy Spirit.