The first records of the area date back to the IX century in the Lombard period. The position of the town was strategic for enemies attacks during the Middle Age. Lately, the town became an important cultural and religious center. It was home for many Bishops until the 1973 when the Diocese of Campagna merged with the Archdiocese of Salerno.
During the Second World War, Campagna was a temporary home for many Jews thanks to Giovanni Palatucci and his uncle Giuseppe Maria Palatucci. People arrived from the north of Italy and Campagna citizens hid those people in the basements of the churches. Giovanni was later honoured as a Righteous Among the Nations by the Yad Vashem Holocaust Memorial. Much of this is documented in Elizabeth Bettina's book, It Happened in Italy. Today, goods left by the Jews are shown in the Museo della Memoria in the Campagna town centre.