The interpretation timeline
James 1:1 Douay-Rheims

James the servant of God, and of our Lord Jesus Christ, to the twelve tribes which are scattered abroad, greeting.

A.D. 100 – 1863 8 witnesses

Patristic

before A.D. 750
100
A.D.
c. A.D. 37–100
“Caesar sent Albinus to Judea as procurator when he was informed of the death of Festus. But the younger Annas, who as I said had received the high priesthood, was headstrong in character and audacious in the extreme. He belonged to the sect of the Sadducees, who in judging offenders are cruel beyond any of the Jews, as I have already made clear. Being a man of this kind, Annas thought that he had a convenient opportunity, as Festus was dead and Albinus still on the way. So he assembled a council of judges and brought it before James, the brother of Jesus, known as Christ, and several others. Annas charged them with breaking the law and handed them over to be stoned. But those who were considered the most fair-minded people in the city, and strict in their observance of the law, were most indignant at this, and sent secretly to the king, imploring him to write to Annas to stop behaving in this way. His conduct had been wrong from the first. Some of them too waylaid Albinus on the road from Alexandria and explained that it was illegal for Annas to assemble a council without his authority. Convinced by their arguments, Albinus wrote an angry letter to Annas, threatening to punish him. In consequence, King Agrippa deprived him of the high priesthood, which he had held for three months only, and appointed Jeshua son of Dammaeus.”
Source

Medieval

c. 750 – 1100
850
A.D.
Ishodad of Merv Medieval
d. A.D. 850
“The opening resembles the titles of St. Paul's letters, and perhaps James is the author of it, whoever he may be. He was unacquainted with Paul's custom of writing to one particular nation and city, and for a particular reason. Instead, this author writes to the twelve tribes scattered among the nations because of the captivity, and not to the churches in every place, because he had no particular reason to be so specific.”
Source

Post-Reformation

c. 1650 – 1900
1714
A.D.
Matthew Henry Reformed
1662–1714
“We have here the inscription of this epistle, which consists of three principal parts. I. The character by which our author desires to be known: James, a servant of God, and of the Lord Jesus Christ. Though he was a prime-minister in Christ's kingdom, yet he styles himself only a servant. Note hence, Those who are highest in office or attainments in the church of Christ are but servants. They should not therefore act as masters, but as ministers. Further, Though James is called by the evangelist the brother of our Lord, yet it was his glory to serve Christ in the spirit, rather than to boast of his being akin according to the flesh. Hence let us learn to prize this title above all others in the world - the servants of God and of Christ. Again, it is to be observed that James professes himself a servant of God and of the Lord Jesus Christ; to teach us that in all services we should have an eye to the Son as well as the Father. We cannot acceptably serve the Father, unless we are also servants of the Son. God will have all men to honour the Son as they honour the Father (Joh 5:23), looking for acceptance in Christ and assistance from him, and yielding all obedience to him, thus confessing that Jesus Christ is Lord, to the glory of God the Father. II. The apostle here mentions the condition of those to whom he writes: The twelve tribes which are scattered abroad. Some understand this of the dispersion upon the persecution of Stephen, Acts 8. But that only reached to Judea and Samaria. Others by the Jews of the dispersion understand those who were in Assyria, Babylon, Egypt, and other kingdoms into which their wars had driven them. The greatest part indeed of ten of the twelve tribes were lost in captivity; but yet some of every tribe were preserved and they are still honoured with the ancient style of twelve tribes. These however were scattered and dispersed. 1. They were dispersed in mercy. Having the scriptures of the Old Testament, the providence of God so ordered it that they were scattered in several countries for the diffusing of the light of divine revelation. 2. They began now to be scattered in wrath. The Jewish nation was crumbling into parties and factions, and many were forced to leave their own country, as having now grown too hot for them. Even good people among them shared in the common calamity. 3. These Jews of the dispersion were those who had embraced the Christian faith. They were persecuted and forced to seek for shelter in other countries, the Gentiles being kinder to Christians than the Jews were. Note here, It is often the lot even of God's own tribes to be scattered abroad. The gathering day is reserved for the end of time; when all the dispersed children of God shall be gathered together to Christ their head. In the mean time, while God's tribes are scattered abroad, he will send to look after them. Here is an apostle writing to the scattered; an epistle from God to them, when driven away from his temple, and seemingly neglected by him. Apply here that of the prophet Ezekiel, Thus saith the Lord God, Although I have cast them far off among the heathen, and although I have scattered them among the countries, yet will I be to them as a little sanctuary in the countries where they shall come, Eze 11:16. God has a particular care of his outcasts. Let my outcasts dwell with thee, Moab, Isa 16:3, Isa 16:4. God's tribes may be scattered; therefore we should not value ourselves too much on outward privileges. And, on the other hand, we should not despond and think ourselves rejected, under outward calamities, because God remembers and sends comfort to his scattered people. III. James here shows the respect he had even for the dispersed: greeting, saluting them, wishing peace and salvation to them. True Christians should not be the less valued for their hardships. It was the desire of this apostle's heart that those who were scattered might be comforted - that they might do well and fare well, and be enabled to rejoice even in their distresses. God's people have reason to rejoice in all places, and at all times; as will abundantly appear from what follows.”
Source
1771
A.D.
John Gill Reformed
1697–1771
“James, a servant of God,.... That is, of God the Father; not by creation only, as every man is; nor merely by calling grace, as is every regenerate person; but by office, as a preacher of the Gospel, being one that served God in the Gospel of his Son, and was an apostle of Christ; nor is this any sufficient objection to his being one, since others of the apostles so style themselves: and of the Lord Jesus Christ; the Ethiopic version reads this in connection with the former clause, without the copulative "and", "James, the servant of God, our Lord Jesus Christ": and so some consider the copulative as explanative of who is meant by God, even the Lord Jesus Christ: but it seems best to understand them as distinct; and that this apostle was not only the servant of God the Father, but of his Son Jesus Christ, and that in the same sense, referring to his office as an apostle of Christ, and minister of the word: to the twelve tribes which are scattered abroad; by whom are meant believing Jews, who were of the several tribes of Israel, and which were in number "twelve", according to the number and names of the twelve patriarchs, the sons of Jacob; and these were not the Christian Jews, who were scattered abroad upon the persecution raised at the death of Stephen, Act 8:1 but they were the posterity of those who had been dispersed in former captivities, by the Assyrians and others, and who remained in the several countries whither they were carried, and never returned. The Jews say (f), that the ten tribes will never return, and that they will have no part nor portion in the world to come; but these the Gospel met with in their dispersion, and by it they were effectually called and converted, and are the same that Peter writes to, Pe1 1:1 Pe2 1:1. And thus we read of an hundred and forty and four thousand sealed of all the tribes of Israel, Rev 7:4 and to these the apostle here sends greeting; that is, his Christian salutation, wishing them all happiness and prosperity, in soul and body, for time and eternity; and it includes all that grace, mercy, and peace, mentioned in the usual forms of salutation by the other apostles. The same form is used in Act 15:23 and since it was James that gave the advice there, which the rest of the apostles and elders came into, it is highly probable that the epistles sent to the Gentiles were dictated by him; and the likeness of the form of salutation may confirm his being the writer of this epistle. (f) T. Bab. Sanhedrin, fol. 110. 2.”
Source
1832
A.D.
Adam Clarke Methodist
1762–1832
“James, a servant of God - For an account of this person, or rather for the conjectures concerning him, see the preface. He neither calls himself an apostle, nor does he say that he was the brother of Christ, or bishop of Jerusalem; whether he was James the elder, son of Zebedee, or James the less, called our Lord's brother, or some other person of the same name, we know not. The assertions of writers concerning these points are worthy of no regard. The Church has always received him as an apostle of Christ. To the twelve tribes - scattered abroad - To the Jews, whether converted to Christianity or not, who lived out of Judea, and sojourned among the Gentiles for the purpose of trade or commerce. At this time there were Jews partly traveling, partly sojourning, and partly resident in most parts of the civilized world; particularly in Asia, Greece, Egypt, and Italy. I see no reason for restricting it to Jewish believers only; it was sent to all whom it might concern, but particularly to those who had received the faith of our Lord Jesus Christ; much less must we confine it to those who were scattered abroad at the persecution raised concerning Stephen, Act 8:1, etc.; Act 11:19, etc. That the twelve tribes were in actual existence when James wrote this epistle, Dr. Macknight thinks evident from the following facts: "1. Notwithstanding Cyrus allowed all the Jews in his dominions to return to their own land, many of them did not return. This happened agreeably to God's purpose, in permitting them to be carried captive into Assyria and Babylonia; for he intended to make himself known among the heathens, by means of the knowledge of his being and perfections, which the Jews, in their dispersion, would communicate to them. This also was the reason that God determined that the ten tribes should never return to their own land, Hos 1:6; Hos 8:8; Hos 9:3, Hos 9:15-17. 2. That, comparatively speaking, few of the twelve tribes returned in consequence of Cyrus's decree, but continued to live among the Gentiles, appears from this: that in the days of Ahasuerus, one of the successors of Cyrus, who reigned from India to Ethiopia, over one hundred and twenty-seven provinces, Est 3:8, The Jews were dispersed among the people in all the provinces of his kingdom, and their laws were diverse from the laws of all other people, and they did not keep the king's laws; so that, by adhering to their own usages, they kept themselves distinct from all the nations among whom they lived. 3. On the day of pentecost, which happened next after our Lord's ascension, Act 2:5, Act 2:9, There were dwelling at Jerusalem Jews, devout men, out of every nation under heaven; Parthians, Medes, and Elamites, etc.; so numerous were the Jews, and so widely dispersed through all the countries of the world. 4. When Paul traveled through Asia and Europe, he found the Jews so numerous, that in all the noted cities of the Gentiles they had synagogues in which they assembled for the worship of God, and were joined by multitudes of proselytes from among the heathens, to whom likewise he preached the Gospel. 5. The same apostle, in his speech to King Agrippa, affirmed that the twelve tribes were then existing, and that they served God day and night, in expectation of the promise made to the fathers, Act 26:6. 6. Josephus, Ant. i. 14, cap. 12, tells us that one region could not contain the Jews, but they dwelt in most of the flourishing cities of Asia and Europe, in the islands and continent, not much less in number than the heathen inhabitants. From all this it is evident that the Jews of the dispersion were more numerous than even the Jews in Judea, and that James very properly inscribed this letter to the twelve tribes which were in the dispersion, seeing the twelve tribes really existed then, and do still exist, although not distinguished by separate habitations, as they were anciently in their own land. Greeting - Χαιρειν· Health; a mere expression of benevolence, a wish for their prosperity; a common form of salutation; see Act 15:23; Act 23:26; Jo2 1:11.”
Source
1849
A.D.
1774–1849
“James, a servant of God, and of our Lord Jesus Christ. Some have doubted whether the author of this epistle was St. James, the apostle, because he does not call himself an apostle. By the same weak argument we might reject all the three epistles of St. John and his Apocalypse, and the epistle of St. Jude. Nor does St. Paul give himself this title in those to the Thessalonians, to the Philippians, to Philemon, or to the Hebrews. — To the twelve tribes, which are dispersed. Literally, which are in the dispersion. That is, to the Jews converted in all nations. — Greetings. [1] Literally, salvation. Which comprehendeth much the same as, when St. Paul says, grace, peace, mercy, &c. (Witham)”
Source
1863
A.D.
1796–1863
“Lit. "in dispersion." To all Jews, but especially converts fx-om Judaism, whether in Judea, or scattered among the nations. After the return from the Babylonian captivity, the Jews were found in great numbers in the chief cities of the world.”

Undated

date unknown
date
unknown
Glossa Ordinaria Medieval
“James. He undertook the care and governance of the church of Jerusalem, after the apostles had been sent out to preach. To the twelve tribes. To have particular concern for these belonged to the twelve apostles, who discharged an embassy for the Lord among the circumcision. Whence Paul also says: James, and Cephas, and John, who seemed to be pillars, gave the right hands, etc. Therefore he writes to them especially, and because he himself had been ordained bishop over them by the rest of the apostles.”
Source
Modern · 1953 →

The in-app commentary runs from the Fathers to the early-modern record, then stops — that's where the public-domain sources end, not where the reading does. For the modern reading, follow the sources directly.