Mussolini re-formed the Milan fascio into the Fasci Italiani di Combattimento (Italian Combat Squad), consisting of 200 members. Mussolini's foreign policy was based on spazio vitale (vital space), a concept analogous to Lebensraum in German National Socialism. The concept of spazio vitale was first announced in 1919, when the entire Mediterranean, especially so-called Julian March, was claimed as Italy's exclusive sphere of influence, as from the ancient Roman province of Italia. Mussolini believed that Italy had the right to colonize the neighboring Slovene ethnic areas and the Mediterranean because they were less developed, and that Italy needed the space because it was suffering from overpopulation. In September 1920, Mussolini made a speech in Pula, in which he also stated that, "...When dealing with such a race as Slavic — inferior and barbarian — we must not pursue the carrot, but the stick policy ... We should not be afraid of new victims ... The Italian border should run across the Brenner Pass, Monte Nevoso and the Dinaric Alps ... I would say we can easily sacrifice 500,000 barbaric Slavs for 50,000 Italians ..."
At night the Western Allies began Operation Plunder, the crossing of the Rhine. The 21st Army Group under Field Marshal Bernard Montgomery launched Operation Plunder, as a part of a coordinated set of Rhine crossings. The crossing of the river Rhine was at Rees, Wesel, and south of the river Lippe by the British Second Army, under Lieutenant General Sir Miles C. Dempsey (Operations Turnscrew, Widgeon, and Torchlight), and the United States Ninth Army (Operation Flashpoint (1945), under Lieutenant General William H. Simpson. The First Allied Airborne Army conducted Operation Varsity airborne landings on the east bank of the Rhine in support of Operation Plunder, consisting of U.S. XVIII Airborne Corps, the British 6th and the U.S. 17th Airborne Divisions. Within a week of the start of Plunder, the Allies had taken 30,000 prisoners of war north of the Ruhr.
Italian partisans operating in Rome threw a bomb at an SS unit, killing 33 soldiers. The next day, the Nazis rounded up 335 Italian civilians and took them to the Adeatine caves where they were executed in reprisal for the death of the SS soldiers. Of the civilian victims, 253 were Catholic, 70 were Jewish and the remaining 12 were unidentified. Despite such reprisals, the partisans were extremely effective in aiding the Allies and by the summer of 1944, resistance fighters successfully immobilized eight of the 26 German divisions in northern Italy. By the end of the war, the partisans guerrilla force controlled Venice, Milan, and Genoa, though at considerable cost to their units. They lost about 50,000 fighters but achieved their victory and won back the Republic. Italian partisans (antifascist guerrilla fighters) aided the Allied battle against the Germans and had been fighting underground against the fascist government of Mussolini long before its surrender. Then it fought against German fascism. The main weapon of the Italian guerrillas was sabotage of communication lines, transports, and supply lines, as well as killing enemy soldiers.