This verse is referring to the Israelites. Allah through His Unlimited Knowledge, had known that the Jews are the foundation and source of evil in the universe, and that this nation will suffer from them. The biggest proof of this can be seen from what Arabs had to suffer in the past and present due to their conspiracies and plotting which have not stopped even for a second, such as what we see in Syria today of destruction and devastation.
When the Prophet r entered Medina, he had a discourse with the polytheists and discourses with the Jews. Due to this, the Jews have earned wrath upon wrath. The former because they had rejected what the Prophet Muhammad r had brought, and this is the shared wrath with the polytheists, and the latter specifically on them because they had been commanded to follow him as mentioned in the Torah.