The British army has throughout history plied soldiers with rum and grog to boost morale and quiet dissent. Did this policy continue into WW2, and if so, what was the drink supplied by the state?
The answer is, quite simply, yes.
The daily ration of alcohol traditionally existed to help soldiers cope with the stress of combat and daily life within the military.
In WW2, the British Army did continue with a Rum ration to troops, but only in some situations and only with the consent of a medical officer. This ration was generally given before attacks and during protracted periods of combat.
The Royal Navy continued the practice of a daily alcohol allowance up until 1970. Today, the order to Splice the Mainbrace can be given by Queen Elizabeth II, a member of the Royal Family or a member of the Admiralty Board, where a tot of rum will be issued to each member of the ships company of an RN vessel.
The paper "Alcohol use and misuse within the Military: A review" by Edgar Jones(King’s Centre for Military Health Research) and Nicola T. Fear (Academic Centre for Defence Mental Health, King ’ s College London) is a fascinating read that gives detail on alcohol consumption within the military for a number of more recent conflicts - including WW1, WW2 and Vietnam.
As per the drink of choice, the officially issued spirit (as I have mentioned) was Rum, although it is likely that this could vary depending on availability.
Grog, was a drink made from a mixture of water or a small beer (weak) and rum that was introduced into the Royal Navy in 1740. The juice from citrus fruits was later added to prevent the spoilage of the mixture.
One other supplement of choice was a pill.
It is not alcohol but due to its strategic importance, maybe that's not off-topic.
It is an established fact that German soldiers used methamphetamine to fight. Blitzkrieg was then the combination of a tactical rush and the devastating effect on adversaries troops' morale to see soldiers tirelessly fight nights and days. Air Force pilots got those pills in priority. (cost/kill ratio) When UK found it out, they launched a research program to have their own magic potion and came up by 1942 with regular amphetamine as the best drug to use. From then on, RAF pilots succeeded to compete with the Germans; amphetamine makes your reflex and attention top notch whereas methamphetamine adds to the sauce an euphoria which can lead to very hazardous and risky behavior which can be good or bad depending on your luck.
Meanwhile, the Netherlands made and sold all those molecules to both armies. It's a very little know fact that is not often taught as school but fundamental in understanding the balance of power of WWII.
P.S. : Later on, amphetamine was freely sold in the UK and US under the name benzedrine.
My source for this info is German/US documentary aired a while ago on Arte. It is available on Youtube. It is in French, although I've just checked out the automatic subtitles translation in English and it does quite a good job !