King Zog's effort to reduce Italian control over his armed forces was insufficient to save them from quick humiliation when the Italians attacked on April 7, 1939. Although annual conscription had generated a trained reserve of at least 50,000 men, the Albanian government lacked the time to mobilize it in defense of the country. The weak Albanian resistance, consisting of 14,000 men against the Italian force of 40,000, was overcome within one week, and Italy occupied and annexed the country. Later in 1939, the Italians subsumed some Albanian forces into their units. They gained little, however, from Albanian soldiers, who were unwilling to fight for the occupying power, even against their traditional Greek enemies. They deserted in large numbers.

Benito Mussolini, the Italian fascist premier, and his Axis partners viewed Albania as a strategic path through the Balkans from which to challenge British forces in Egypt and throughout North Africa. Albania served as the bridgehead for Mussolini's invasion of Greece in October 1940, and Italy committed eight of its ten divisions occupying the country.

The Albanian Communist Party and its armed resistance forces were organized by the Communist Party of Yugoslavia in 1941 and subsequently supported and dominated by it. Resistance to the Italian occupation gathered strength slowly around the partycontrolled National Liberation Movement (NLM, predecessor of the NLF) and the liberal National Front. Beginning in September 1942, small armed units of the NLF initiated a guerrilla war against superior Italian forces, using the mountainous terrain to their advantage. The National Front, by contrast, avoided combat, having concluded that the Great Powers, not armed struggle, would decide Albania's fate after the war.

After March 1943, the NLM formed its first and second regular battalions, which subsequently became brigades, to operate along with existing smaller and irregular units. Resistance to the occupation grew rapidly as signs of Italian weakness became apparent. At the end of 1942, guerrilla forces numbered no more than 8,000 to 10,000. By the summer of 1943, when the Italian effort collapsed, almost all of the mountainous interior was controlled by resistance units.

The NLM formally established the National Liberation Army (NLA) in July 1943 with Spiro Moisiu as its military chief and Enver Hoxha as its political officer. It had 20,000 regular soldiers and guerrillas in the field by that time. However, the NLA's military activities in 1943 were directed as much against the party's domestic political opponents, including prewar liberal, nationalist, and monarchist parties, as against the occupation forces.

Mussolini was overthrown in July 1943, and Italy formally withdrew from Albania in September. Seven German divisions took over the occupation from their Italian allies, however. Four of the divisions, totalling over 40,000 troops, began a winter offensive in November 1943 against the NLA in southern Albania, where most of the armed resistance to the Wehrmacht and support for the communist party was concentrated. They inflic891 icted devastating losses on NLA forces in southern Albania in January 1944. The resistance, however, regrouped and grew as final defeat for the Axis partners appeared certain. By the end of 1944, the NLA probably totaled about 70,000 men organized into several divisions. It fought in major battles for Tiranė and Shkodėr and pursued German forces into Kosovo at the end of the war. By its own account, the NLA killed, wounded, or captured 80,000 Italian and German soldiers while suffering about 28,000 casualties.

The communist-controlled NLF and NLA had solidified their hold over the country by the end of October 1944. Some units, including one whose political officer, Ramiz Alia, would eventually succeed Enver Hoxha as leader of Albania, went on to fight the Germans in Albanian-populated regions of Yugoslavia, including Kosovo. Hoxha had risen rapidly from his post as political officer of the NLA to leadership of the communist party, and he headed the communist government that controlled the country at the end of World War II. Albania became the only East European state in which the communists gained power without the support of the Soviet Union's Red Army. They relied instead on advice and substantial assistance from Yugoslav communists and Allied forces in occupied Italy.

Data as of April 1992