For the most part of its 40 km (25 mi) length, the Garigliano River marks the border between the Italian regions of Lazio and Campania.

Western Roman Emperor Majorian engaged a Vandal raiding party in battle at Garigliano in 457.

In the 9th and early 10th centuries, a band of Saracens established themselves on the banks of the river, from where they launched frequent raids on Campania and central Italy.

The bigger French Army was practically destroyed at little cost to the Spanish, with the remnants later surrendering at Gaeta.

Rumours tell that the waters of the river ran red in the Cassino area during the famous battle, because of the blood of the many corpses of soldiers.