1 Peter shows that Peter accept pastoral responsibility for the new Christians in northern Anatolia. This follows the account in Acts of Paul seeking to extend his work there, but being diverted by the Holy Spirit to pursue work in Macedonia and Achaia (Greece).
1 Peter was not just written to Christians in northern Anatolia, but to the whole of Anatolia (modern Turkey, also called Asia Minor). We know the gospel reached southern Galatia, southern Phrygia and the province of Asia through the journeys of Paul, Barnabas and Silvanus, but Acts is silent on how the gospel reached the provinces of Cappadocia and Bithynia, the northern part of the province of Galatia and the client kingdom of Pontus. All we know from Acts is that Paul and his companions were held back from going into some of those regions.
The examination of the question of the evangelisation of these Anatolian regions must begin with the report in Acts 2:5-12, where it is reported that there were Jews from Cappadocia and Pontus settled in Jerusalem on the day of Pentecost who heard Peter proclaim the Gospel. Yet is not said in Acts that churches came to be established in these regions as a result of the Pentecost event, or even from subsequent events. We can guess that Aquila and Priscilla, Jews originally from Pontus, who were later found in Rome, could have had some influence in establishing the gospel in their native land. Beyond this, all we can do is postulate that the scattering of the Christians after Stephen’s martyrdom could have resulted in some of them returning to their homelands.
It is possible that there were a number of Jews in the churches in regions addressed by 1 Peter, and Jewish Christians also among them. The extensive citations from the Old Testament found in Peter’s letter, which would have been more understandable for Jews than for non-Jews, could indicate the presence of a number of Jews in these brotherhoods of believers. Yet 1 Peter implies that non-Jews were in the majority in these congregations, saying to them that, even though they were previously not a people, now they were the people of God (1 Peter 2:10). So one can conclude that these new congregations consisted of more than just returning Jewish converts and their Jewish disciples.
Beachheads in at least Bithynia, but probably in all the north Anatolian political regions, were established through dedicated missionary efforts before Paul wrote Romans (written ca. 57). In Rom. 15:23, Paul said that there was no further place for him to work in “these regions.” He made this comment in the context of having just said that he did not want to preach the gospel in regions where others had established the foundations (Rom. 15:20). Before this, he had been working in southern Galatia, the provinces of Asia, Macedonia and Achaia, and around to Illyricum. As far as we know, he had not worked in Bithynia, even though Acts 16:7 shows that he had thought about a missionary venture there. The Romans passage indicates that he had abandoned that ambition. While he had followed his earlier intention to proceed through and into the province of Asia, establishing a strong work based in Ephesus, there is no indication that he again tried to reach Bithynia. This gives us confidence to suggest that other missionaries had undertaken the task of evangelisation of the nations of northern Anatolia, and that this had happened before 57.
With such an early date for the evangelisation of this region, it is likely that we should attribute this to other missionaries reaching the region, who were probably working in northern Anatolia while Paul was engaged in Ephesus. Of course, known missionaries, specifically Silvanus, Paul’s companion, and Barnabas and Mark come to mind, while we cannot discount the possibility that others, now unknown, were responsible for taking the Gospel to the nations in these parts. The regrettable silence in Acts concerning any other activity beyond that initiated by Paul after the commencement of Paul’s second missionary journey means that we do not have any help from there. For example, Silvanus drops out of Acts when he, Paul and Timothy were in Corinth; Acts 18:5 is the last time he is mentioned. He is later found in company with Peter (1 Pet. 5:12), probably in Antioch according to this reconstruction. Did Silvanus carry out any missionary activities while making his way back to Syria? If he returned by land, it is possible that he did so. Against this, it is necessary to recognize that Peter recommended Silvanus to the readers of the letter, in 1 Pet. 5:12.
Certainly, from this reconstruction, we have no reason to doubt the testimony of 1 Peter that Apostle Peter had a primary involvement in the evangelisation of the parts of Anatolia that had not been reached by Paul, and well as an abiding interest in those parts of Anatolia that had been evangelised by Paul.