Short answers, pulled from the story.
Operation Achse was the German military operation to forcibly disarm the Italian armed forces following Italy’s armistice with the Allies on the 3rd of September 1943. The coded signal “Achse” was broadcast at 19:50 on the 8th of September, triggering simultaneous attacks on Italian forces across Italy, the Balkans, and occupied territories in France and the Aegean.
The operation was originally named Operation Alarich after Alaric, the Visigothic king who sacked Rome in 410 AD. The codename was later quietly changed to “Achse” to avoid offending the Italians while the Germany-Italy alliance was still formally in place.
On the Greek island of Cephalonia, units of the 33rd Infantry Division “Acqui” chose to resist the Germans. After fighting that killed 1,315 Italian soldiers in action, the surviving soldiers ran out of ammunition and surrendered. More than 5,100 of those captured prisoners were summarily executed by the German Army.
The total number of Italian soldiers captured was enormous across all theaters. Army Group B alone captured over 400,000 soldiers in northern and central Italy by the 19th of September 1943. In the Balkans, 393,000 soldiers were captured and deported to Germany. Army Group C in southern Italy captured 102,340 soldiers, though only 24,294 were held captive, with the rest released.
The Armistice of Cassibile was signed on the 3rd of September 1943. General Giuseppe Castellano signed for Italy and General Walter Bedell Smith signed for the Allies, in the presence of Harold Macmillan and Robert Daniel Murphy as representatives of the British and American governments.
German forces launched attacks on Rome’s defenses at 20:30 on the 8th of September. By the early hours of the 9th of September, the king, Badoglio, and senior officials fled in seven cars, eventually boarding the corvette Baionetta at Ortona and reaching Brindisi on the 10th of September. German forces obtained Rome’s formal capitulation by the afternoon of the 10th of September, with all Italian troops disarmed by the 15th of September.