The 'Battle of Åndalsnes' was fought between British and German forces within the context of the German 'Weserübung' invasion of Norway (19 April/early May 1940).

After the German invasion of Norway on 9 April 1940, a small British expeditionary force was landed at Åndalsnes, in the Romsdal, to support Norwegian units defending the city of Trondheim. British forces were also landed at Namsos, to north of Åndalsnes, in 'Maurice' as the complementary element designed to pinch out the German forces at Trondheim where they had been landed in 'Wildente'. The little campaign which followed the pair of British landings was unsuccessful, and the Allies suffered a significant defeat at Åndalsnes.

Before the British operation had even begun it was beset by a host of problems. The commanders for the landings at Namsos and at Åndalsnes were replaced on several occasions and, ultimately, the units deployed were wholly unprepared in contrast with their German counterparts. Brigadier H. de R. Morgan’s 148^th Brigade, was part of Major General P. J. Mackesy’s 49^th Division. A Territorial Army formation recruited in the West Riding of Yorkshire, the division comprised mainly part-time soldiers who, in addition to being almost completely green and inexperienced, had received very little training for the type of operation in which they were to undertake. There were few modern weapons available and the 148^th Brigade was understrength, having only two instead of the usual three infantry battalions, giving it a strength of just more than 1,000 officers and men.

To prevent the British from advancing inland, German Fallschirmjäger paratroopers were delivered by parachute onto the village and railway road junction of Dombås on 14 April.

The southern part of the planned pincer attack began on 19 April on the day following its 'Sickle' (i) landing, and Morgan’s brigade ran into major problems almost immediately. One of the brigadier’s primary problems was his uncertainty about the commander to whom he was directly subordinated: the possibilities were the British military attaché in Norway, London or essentially no one if his brigade was just to continue as previously ordered. Choosing to obey his orders to support the Norwegian forces as much as he could, he divided his two battalions and moved them to support the Norwegians with his units strung out across the front. His units were then moved to Lillehammer in order to face a German attack from Oslo.

The German attack from Oslo was catastrophic for the underprepared British who, short of men and under-equipped, faced a heavy mortar bombardment which forced the Norwegian commander to order a retreat during which many of the 148^th Brigade’s men were captured for lack of transport. The survivors who managed to escape the Germans regrouped at Faaberg, to the north of Lillehammer, on 22 April. They were then attacked again by the Germans who, making use of artillery support, outflanked and encircled many of the British positions until the 148^th Brigade once more pulled back to Tretten, some 10 miles (16 km) farther to the north. The last German attack came in the evening of 22 April when the Germans, supported by four tanks (one PzKpfw IV Battle tanks and three PzKpfw I or II light tanks) to which the British could do no damage, pushed them back to Heidal where, at last, the Germans halted.

By this time the 148^th Brigade had been reduced to justy nine officers and 300 other ranks, and both Morgan and his headquarters had been captured at Lillehammer.

On 20 April, Major General B. T. C. Paget, commander of the 18^th Division, was given command of the remnants of 'Sickle' following the 148^th Brigade’s defeat and tried in vain to get them air support until, in early May, with heavy casualties and lacking control of the air, the British forces at Åndalsnes were withdrawn.