From the 1974 merger of Sheffield, Rotherham and Doncaster municipal bus companies until the mid-1990s, the operating area of South Yorkshire was split between South Yorkshire Transport and Yorkshire Traction with the former dominating Sheffield and Rotherham.
For nearly two decades following its formation in 1974 through the merger of three municipal bus companies from Sheffield, Rotherham, and Doncaster, the area that is now South Yorkshire was split between two transport operators: South Yorkshire Transport and Yorkshire Traction. The latter had a stronger presence in Sheffield and Rotherham.