There is a great booklet in the Marines in WWII Commerative Series by Lt Col Harry Edwards called "A Different War: Marines in Europe and North Africa". Sheds some light on Marine Corps activity in the ETO.
My Dad was with the 5th Marine Defense Battalion, attached to the 1st Marine Provisional Brigade that sat in Iceland from June 1941 to March 1942.
They were originally slated for the Azores but went to Iceland instead. I don't know what the Azores climate was but my Dad disliked Iceland. Did not eat mutton for the rest of his life. Blamed the diet for poor dental health and hair loss, no fresh vegies or vitamin supplements in those days. He was able to wear the European Campaign Ribbon on his blouse. Lost the rest of his hair after being scared ****less at Tarawa. God bless them All.
Bob