In 1704, during the reign of Queen Anne (1702-14), Dame Elizabeth Fuller funded and established the Watford Free School to educate 40 boys and 20 girls (aged 7 to 14 years) from poor families in the town and parish of Watford.
In 1881, during the reign of Queen Victoria, this educational establishment evolved into two new schools for pupils between 7-16 years – one for 200 boys and the other for 100 girls. The new schools were on built on Derby Road and were opened in April 1884.
Two centuries after the original school opened, in 1904, the Derby Road School had become overcrowded with 312 boys and 148 girls being educated there.
In the reign of Edward VII, the current WGGS main building was opened in September 1907 and WGBS new school was built on its present site and opened in March 1912, during the reign of George V.