The Pola flotilla (U-Flottille Pola) was an Imperial German Navy (IGN) formation set up to implement the U-boat campaign against Allied shipping in the Mediterranean during the First World War in support of Germany's ally, the Austro-Hungarian Empire. It was formed in 1915 from the previously established U-Halbflottille Pola (German U-Boat Half-Flotilla, Pola). It operated mainly from an advanced base at Cattaro in the Adriatic, rather than from Pola. In all, 45 U-boats served in the Pola Flotilla, eleven of which were lost operationally.