West Nassau High School opened its doors in August 1936 as Callahan High School at the current location of Callahan Elementary School. The school was combined at the time with Callahan Elementary using the name Callahan School. According to the Nassau County School Board, teachers were hired in July 1936 under the names of Callahan High and Callahan Elementary. The school’s mascot was the Ramblers. The school colors were then Blue and Gold. The final month of classes at Callahan High was June 1968. During this period of time the State of Florida was mandated by Federal Law under the Civil Rights Act of 1964 to desegregate its school systems statewide and allow African Americans to attend its all-white public school systems. The African American students from Hilliard and Callahan who were previously attending the all African American school of Pine Forrest Community School in grades K through 12 in Callahan were allowed to receive an education equal to their white counterparts. Mr. Emmitt Coakley, who was the football coach at Pine Forrest Community School would later become the principal at West Nassau High School. In August 1968, Hilliard High School and Callahan High School were combined at a new location to form West Nassau County High School. The Flashes of Hilliard and the Ramblers of Callahan became the Warriors of West Nassau County High School. The school colors at West Nassau represent the consolidation of the two schools with the dardinal red representing Hilliard High School and gold representing Callahan High School. The Class of 2009 marked the 40th anniversary of West Nassau County High School. Hilliard students attended high school at West Nassau (Callahan) for three years and then Hilliard Combined 6-12 School was re-opened. Even though Hilliard reopened their combined middle/high school, the high school in Callahan continued-to-be named West Nassau County High School and the name was not changed back to Callahan High School. The school has been serving students from the Bryceville and Callahan area since 1968.
The school currently serves 1050 students. In recent years, the cheerleading team has won 6 state championships, and a national championship.