To whom was the gospel of the circumcision committed?

According to the context, the gospel of the circumcision was committed to Peter. This is contrasted with the gospel of the uncircumcision committed to Paul for the Gentiles. Peter's apostleship was to the Jews, while Paul's was to the Gentiles.

Les explains that the gospel of the circumcision was committed to Peter, while the gospel of the uncircumcision was committed to Paul for the Gentiles. He notes that the Twelve had experiences, such as walking on water, but Paul had the doctrine and revelations from the ascended Lord. The same Christ, God, and Lord Jesus commissioned the Twelve to Israel and Paul to the Gentiles. Les also points out the order of names in Galatians 2:9: James, Peter, and John, with Peter not first.

Galatians 2:7

But contrariwise, when they saw that the gospel of the uncircumcision was committed unto me, as the gospel of the circumcision was unto Peter;

Which gospel was committed to Paul and which was committed to Peter?

The gospel of the uncircumcision—the message to the Gentiles—was committed to Paul, while the gospel of the circumcision—the message to the Jews—was committed to Peter. The same Christ and God worked effectually through both men, commissioning Peter to Israel and Paul to the Gentiles.