In the 1960s Cathedral High School was built in Scranton to serve Catholic students at the secondary level in the central city.

In early 2007, the Meitler Consultants recommended that the equally sized Bishops Hannan and O’Hara merge to form a new high school to serve all of Lackawanna County.

Holy Cross offers a variety of Advanced Placement classes and many electives in Fine Arts, Computer Science, and Humanities.

Scholarship Program has been in effect, where interested students can attend part of the school day at Marywood University to take advanced classes.

On March 30, 2019, Holy Cross won its first Mock Trial State Championship defeating Germantown Friends School at the Dauphin County Courthouse in Harrisburg, PA.

The team then went on to place 9th in the 2019 National High School Mock Trial Competition in Athens, GA as the representatives from Pennsylvania.

The boys varsity basketball team captured the 2008 District 2 PIAA championship in its first appearance since Hannan and O'Hara combined to form Holy Cross.

This Bishop Hannan Golden Lancers team was led by Syracuse University former point guard Gerry McNamara who had won the NCAA national championship just a few years later.