The RHD first came to prominence when it claimed responsibility for a blast bomb attack on 7 September 1998 which killed Frankie O'Reilly, a Royal Ulster Constabulary (RUC) officer. (This attack was part of the Drumcree conflict over Orange Order parades in Portadown.) The group claimed responsibility for the killing of Brian Service (35), a Catholic civilian, on 2 November 1998. The RHD also claimed responsibility for the killing of Rosemary Nelson, a Catholic human rights solicitor, in Lurgan on 15 March 1999. In addition to the killings the RHD has also claimed numerous blast bomb attacks on Catholic families across Northern Ireland. The RHD appeared at around the same time as the Orange Volunteers and initially commentators believed that the same people were involved in both paramilitary groups.
The group has issued statements which seem to take inspiration from the Bible, Deuteronomy Chapter 7,Verse 2: "And the Lord thy God shall have delivered them to thee: thou shalt utterly destroy them. Thou shalt make no league with them, nor show mercy to them ... neither shalt thou make marriages with them."
According to the Sutton database of deaths at the University of Ulster's CAIN project , the RHD was responsible for 8 killings up to 2001. Six of its victims have been civilians, one was a member of the Ulster Defence Association and one was a member of the Royal Ulster Constabulary.