Did the Jerusalem church require circumcision and the law for Gentile believers?
Yes, the Jerusalem church insisted that Gentile believers must keep the law and be circumcised. The context explains that twenty years after Pentecost, Jewish believers in Jerusalem still could not accept Gentiles being saved by Paul's gospel apart from circumcision and law-keeping, prompting the Jerusalem Council.
Les explains that in chapter 15, Paul and Barnabas were called up to Jerusalem after their missionary endeavors throughout Asia Minor. They returned to Antioch, where Gentiles were coming into the congregation, and news of this reached Jerusalem. Peter, James, John, and the rest of the Jerusalem believers could not comprehend that God was saving Gentiles. Les notes that the Jerusalem council took place in A.D. 51, about twenty years after Pentecost. Even then, the Jewish people of Jerusalem were still not ready to accept Gentiles being saved by Paul's gospel apart from keeping the law and circumcision. This disagreement was the reason for the council.