Battle of Kleisoura Pass The Battle of Kleisoura Pass ( ) took place from the evening of 13 April 1941 , when first contact was made , until the midday of 14 April , when Greek organized resistance collapsed . The battle was fought over the narrow pass that crosses between Mt . Vitsi and Mt . Siniatsiko , between elements of the Greek 20th Infantry Division which were occupying the pass and the German " Leibstandarte SS Adolf Hitler " , a mechanized infantry unit of brigade level . The pass was strategically important for it stood on the main Allied defensive line ( Mt . Vitsi – Mt . Siniatsiko – river Aliakmon – Mt . Olympos ) , behind which passed the withdrawal route of the Greek army engaged against the Italians in Albania . Background . The rapid German advance through south Yugoslavia prompted Gen . Wilson , commander of W Force , comprising the Australian 1st Corps ( 2nd New Zealand Division , 6th Australian Division and British 1st Armoured Brigade ) and Greek Army Section Central Macedonia ( 12th and 20th Infantry Divisions ) , to order a withdrawal from the original defensive line on Mt . Vermion to a new line to the west and south , to accommodate for the developments in Yugoslavia and the emerging danger of a German flanking thrust down the Florina valley , behind the Mt . Vermion line . For the Greek divisions on the eastern slopes of Mt . Vermion the withdrawal had very detrimental effects , as it meant the abandoning of well prepared positions , and long night marches ( for safety against air strikes ) . The situation was aggravated by the bad weather which was turning into snowstorms on Mt . Vermion , thus further demoralizing the men and slowing down the march . The withdrawal was covered by a mixed division - sized unit called “ Mackay Force ” at Klidi Pass . Mackay Force ’ s failure to hold the German advance long enough meant that the Greek units did not have time to reach and organize their assigned positions — some of them actually being cut off by the German advance and never reaching them . The Greek 20th Division ' s task was to occupy and defend the passes of Kleisoura and Vlasti . With the Dodecanese Regiment of the division detached and attached to Mackay Force at Klidi pass , the 80th Regiment was tasked with defending Kleisoura Pass and the 35th Regiment with the defence of Vlasti Pass . Realizing the importance of the Kleisoura Pass and the organization of the location , the commander of Army Section Central Macedonia sent ahead on motor vehicles the infantry battalions I / 87 and II / 80 as well as two sapper companies and a battalion ( two batteries ) of mountain artillery on 10 April , to prepare the defences . When the Germans made their first contact on 13 April , the bulk of the 20th Division had not yet arrived at the pass . The Dodecanese Regiment in particular had been scattered in transit , and could not be used until it was reorganised . Prelude . Greek forces . While battalions I / 87 and II / 80 were already present at the pass since 10 April , the bulk of the 80th Regiment ( battalions I and III ) and the 6th Positional Machine - gun battalion began arriving after a night march to Kleisoura village from midday 13 April . At 15 : 00 about one - third of the regiment had arrived . By the fall of the night the regiment had reorganized and took its assigned positions in the center of the location . Stragglers continued arriving until the morning of 14 April . Battalions were at half - strength in manpower and one - third in heavy weapons ( machine - guns and mortars ) . Ammunition , medical and communications materiel stocks had largely been abandoned at Komnina and Ptolemaida . The 20th Division ’ s commander gave orders to immediately supply ammunition from nearby Kastoria . Between 13 and 14 April the forces on the pass were : Col . Panagiotis Dedes , formerly commander of the 21st Brigade , was appointed at the early hours of 14 April to command all Greek units at Kleisoura pass . However he was unable to reach the pass in time due to demolitions on the road , and during the entire battle the commander of 80th regiment , Lt . Col . Vasilios Mantzouranis , was the effective overall commander . German forces . The German units to participate in the battle belonged to the " LSSAH " : Battle . 13 April . Demolitions were carried out along the road between Lehovo and Kleisoura in order to delay the German advance . The first contact was made at 17 : 00 on 13 April . German forward elements attacked the Greek line , particularly battalion I / 87 on height Sargonitsa . With intense effort and artillery support , the attacking Germans managed at 21 : 00 to throw back the I / 87 in disarray , its elements retreating towards heights 1597 and 1623 . The 1st company of the battalion , deployed on the left of its line , surrendered to the Germans except for one platoon . Following this development , battalion III / 80 which was on reserve , moved at 23 : 00 to occupy heights 1597 and 1623 , setting the positions captured by the Germans under fire . The Germans remained idle , and did not continue their maneuver . Throughout the night exchange of artillery fire continued , which depleted the Greek ammunition stocks . A total of 50 Greek officers and soldiers were killed during the fighting of 13 April . The commander of the 20th Division had worries about the morale of its units on the pass , and subsequently requested from Army Section Central Macedonia to obtain a battalion from Army Section West Macedonia ( TSDM ) retreating from Albania . At this day artillery Major and commander of the Greek Alpine Battalion , Ioannis Paparrodou , was killed by enemy fire . 14 April . From 04 : 30 the German artillery began pounding the Greek positions , followed by infantry assault . The Germans attacked from both roads on the eastern exit of the pass , using smoke screens and intense machinegun fire for cover . One attack was directed astride the road and north of the ravine Bisti towards Daouli col , supported by " tanks " ( i . e . assault guns ) , while the other was directed south of the ravine and towards the village of Kleisoura and the height Tzouma Manou . From their positions on Sargonitsa height , the Germans opened fire on the flank of the Greek 6th Machine - gun battalion defending Daouli col . From 07 : 00 the Greek artillery stopped its fire due to the depletion of its ammunition . The German armour fired intensely on the Greek positions while there were no anti - tank weapons to counter them . The German Air Force constantly flew over the battlefield causing further demoralization . Beginning at 09 : 00 , the 6th P . MG . battalion ' s line began to unravel , its machine - guns getting knocked out one by one and elements retreating to the rear . At 10 : 30 , ammunition ( 2 , 000 rounds per machine - gun ) had been depleted , and the remainder of the battalion surrendered . Battalion I / 80 to the south was not attacked in force , however its commander recognizing the danger of encirclement from the north ordered a withdrawal . While withdrawing the battalion was attacked by " tank " fire to the rear from very short range , and its remnants , except the 1st company , surrendered at 10 : 45 . The commander of the 20th Division tried to reorganize the units west of the pass , sending the artillery to the west to cover the infantry , while using a sapper company and the 20th Reconnaissance Group to block the retreat . However the German artillery and air force scattered the Greek columns and the wave of flight overran the blocking units . Army Section Central Macedonia ( TSKM ) , taking knowledge of the situation , ordered the 20th Division to counter - attack and retake its lost positions . Such a mission however was beyond the capabilities of the scattered division . With the permission from GHQ , the commander of TSKM ( Mj . Gen . Karassos ) asked W Force commander , Lt . Gen . Wilson , to commit Brig . Charrington ' s 1st Armoured Brigade for a counter - attack . Although Wilson gave the order , Charrington interpreted it as a " suggestion " rather an order , and ignored it . TSKM then sought assistance from TSDM . Karassos asked three battalions of infantry from TSDM , which , combined with as much infantry as the 20th Division could muster as well as its artillery , would counter - attack and recapture the pass . Although agreement was reached , there were not enough transports available to bring the necessary forces from Albania , the closest being the 13th Division around Bilisht . By 20 : 00 on 14 April , only elements of the I / 23 battalion had arrived to the area of the 20th Division , on the saddle of Kastoria , and consequently the counter - attack was never conducted . Instead , the Germans continued their advance , attacking the I / 23 battalion and other elements of 13th division the next day , 15 April , in the Battle of Lake Kastoria . Aftermath . The failure to hold the pass had grave consequences for the Greeks , as the German advance directly threatened the main retreat route of TSDM . Although the Greeks would attempt again to stop the Germans on 15 April east of the road , this time they would fight on open terrain less favourable than the Kleisoura pass . The Greek casualties were heavy , the 80th Regiment being effectively destroyed . The Germans claimed to have taken 1000 prisoners . The Greek 20th Division pulled the bulk of its 35th Regiment from Vlasti pass ( leaving behind one battalion ) and concentrated around Smixi , south of 13th Division . For the remainder of the war the division would be a non - combat - worthy formation .