was there a group that opposed it?
Yes, the Anti-Federalists. Though initially it was opposed by the Federalists as well.
United States Bill of Rights
Following the Philadelphia Convention, some leading revolutionary figures such as Patrick Henry, Samuel Adams, and Richard Henry Lee publicly opposed the new frame of government, a position known as "Anti-Federalism". 
who should be credited for the federal bill of rights James Madison. when was it framed? UNANSWERABLE
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United States Bill of Rights [SEP] Anti-Federalists
Following the Philadelphia Convention, some leading revolutionary figures such as Patrick Henry, Samuel Adams, and Richard Henry Lee publicly opposed the new frame of government, a position known as "Anti-Federalism". Elbridge Gerry wrote the most popular Anti-Federalist tract, "Hon. Mr. Gerry's Objections", which went through 46 printings; the essay particularly focused on the lack of a bill of rights in the proposed Constitution. Many were concerned that a strong national government was a threat to individual rights and that the President would become a king. Jefferson wrote to Madison advocating a Bill of Rights: "Half a loaf is better than no bread.