The Greco-Italian war was the brainchild of Benito Mussolini the dictator of Italy. He attack Greece through Albania after attempting to create a provocation for some time.
The initial invasion by him went poorly and Italy continued to perform poorly during the spring of 1941 offensive.
It was from this point that the war differed to OTL as the Germans didn't intervene in the situation in Greece. After the poorly conducted and failed Italian spring offensive the Greeks in response were afraid of a German intervention even though they had received little intelligence suggesting so. They attacked the Italian army again on the 17th April after building up supplies and troops.
They launch an offensive toward Vlore which although fails to reach the port makes significant ground over five days reaching Peshkepi before they halt at the river while the Italians counter-attack consistently they fail to win any battles and lose a large number of troops.
The Italians themselves launch their own attack on the 8th May and try to cross the river and force the Greeks back but are badly mauled in the fighting by Greek artillery and heavy fighting.
They also launch another offensive on the 19th May south of Berat to take mount Trebeshina in hope the Greeks will lack troops but are repulsed after heavy fighting.
The Greeks finally resume their offensive on the 10th June and attack from south so bypass the river and force their way to Vlore and drive the Italians out on the 21st June. The next day Germany invades Russia making the Greeks feel more secure in their offensives.
The Greeks launch their next attack on the 12th July toward Berat and reach Terpan before the Italians solidify. The Italians launched a mass counter- attack on the 18th July but failed to take much ground from Greek held Albania. On the 8th August the Greeks pushed for Berat and on the 17th August it fell to the Greek forces.
Greek forces were depleted and so after discussing with the Western Desert Command they agreed all offensives unless an opportunity was presented would be halted until the British could help and intervene.
The Italians would attack Greek positions twice more in an attempt to break the stalemate but wouldn't manage to succeed with either of them.
After the British victory in North Africa they started moving troops to Greece with the first ones arriving in February. At the start of May 5 Commonwealth divisions launched an offensive toward Durres on the 2nd May. This was designed to trap the bulk of the Italian army in Albania. The Italian forces finally collapse with massive pushes and by the 11th May the British had taken Durres and Italian forces desperately tried to pull back out of Albania. On the 12th May Yugoslavian troops attacked northern and eastern Albania and crushed Italian forces. The British moved from Durres to Tirana and took it on the 15th May.
The Italian coastal pocked surrendered en mass to the British and Yugoslavian forces break through driving the Italians south. On the 3rd June the whole of Albania is under Allied control with the general defeat of Italian forces.