What does Galatians address along with law-keeping and circumcision?

Galatians addresses the false teaching that had come into Paul's churches, namely the false teaching of law-keeping and circumcision, plus Paul's Gospel of Grace. It was written primarily to straighten out this error and to clarify the true gospel for the churches.

Les explains that this little letter, Galatians, was written primarily to straighten out the false teaching that had come into Paul's churches that he had started. That false teaching combined law keeping and circumcision with Paul's Gospel of Grace. So Galatians addresses that mixture, correcting the error that had entered the churches.

Galatians 2

Why did Paul refuse to require circumcision and Law-keeping of his Gentile converts?

Paul refused to require circumcision and Law-keeping of his Gentile converts because they were now saved by grace through faith plus nothing. God was changing the program, moving from Judaism and legalism into the age of grace, so such requirements were no longer necessary.