So, let’s say a certain type of person steals a Time Machine and travels to Berlin August 1st, 1939. He shows his time machine to Adolf Hitler, and tries to give him advice necessary to win WW2 before it even starts. My question is, what advice should he give?
Put Guderian in charge of the invasion of France and let him handle things. Don't interfere or tell him to halt the advance under any circumstances. If the UK offers a negotiated surrender, take it.
Also, don't attack Russia. If you absolutely cannot resist attacking Russia, then be patient; don't do it until after France and the UK are defeated. Again, don't interfere directly with military planning.
If you occupy parts of the Soviet Union, don't mistreat the natives. Instead, encourage them to join your fight against the Soviets.
Don't declare war on the US just because Japan does. The US has no land Germany wants anyway.
Don't fight a war on two fronts.
The obvious answer is that the German resources were stretched by attacking Russia while it was pushing into France. On top of it all, they attacked at a point when all the Russians had to do was keep them outdoors during a Russian winter and let many of the enemy soldiers die.
Is it possible Russia would have attacked Germany or any occupied territories if Germany had not made that first strike? Perhaps, but (in my opinion) it's doubtful. Russia had an over-supply of manpower, and a gross under-supply of materiel. This is to the point where in many cases they had less rifles than they had soldiers.
Also, it can be argued that if Russia had come into the war and attacked German occupied territories, at least the Nazi supply chains would not have been as stretched defending on their own ground, and the German soldiers were (according to many reports) better equipped, trained and disciplined than their Russian counterparts of the day, meaning that they would have made a better show of the fight on ground they understood while they were not freezing literally to death.
What does this buy the Germans? Focus. They could have poured all those military resources into the West, possibly taking England in the process (or accepting their conditional surrender). If they had done that, then Winston Churchill doesn't form a de facto international war cabinet and convince Roosevelt to solve Europe first; England falls, America stays out of Europe, content to solve their own problems with the Japanese and then go back to a relatively isolationist policy, and Russia just gets on with building a Communist industrial complex at its own steady rate.
Of course, war between Germany and Russia is inevitable at some point, but why not hold off until you can put all your focus into it, your scientists have perfected rocket and jet technology, and you can plan your attack so it doesn't coincide with winter?
There are some complexities of course; Germany was still pretty much broke and was building its military industrial complex on the expectation of future gains and spoils, but to me that's all the more reason to focus on one enemy at a time.
Your Enigma isn't as secure as you think.
(Followed by: let me explain public key cryptography to you).
The allied forces had a significant advantage through code-breaking while the Germans considered it unbreakable. Whether you know or are unaware of the coming ATTACK AT DAWN, this may eventually turn things around. It's your story that makes this work :-)
No information would help Nazi Germans to win the war - only to avoid it, like fascist Spain did.
My first argument - Nazis are Nazi, you can't make them "softer", and they did the best they could
Long term war was not a German choice. They planned to end the war with Russia at the end of summer of 1941 (and they almost did it!) and to conquer all "living space" they needed to the end of 1942 (Europe up to Urals and Middle East up to Afghanistan or India), and have a peace treaty with countries left in 1942-43.
Germans (and Hitler in particular) were not stupid: they knew more than we do now about battling on two fronts, and that they have not much resources. So they were not fighting on two fronts for five years (39-44) - they concentrated all resources (90%) on one main direction (East-West, then East again) with minor operations on other fronts.
Germans were already developing nuclear weapons, rocket and jet engines - before the war. They just had no resources and time to implement all this technology in needed quantities.
So any new information would not change much.
For example: if Hitler would decide not to attack USSR in 41, but instead "finish" Britannia, Germans would loose a lot in sea operations. While USSR would finish there army modernization and would certainly attack Germans (Stalin also was not stupid - he would knew who would be next) with many thousands of new T-34 and KV-1,2.
Yes the WWII scenario can be changed but Germany or, more precisely, Nazi defeat is inevitable. And the root cause is Nazi ideology. No one would tolerate it. Nazi managed to unite too many countries against them. And if they didn't follow this ideology, they would not be Nazi and would not start that war in the first place.
My second argument - Any information on military actions would make this information useless.
War is a highly random process. And such a process has "butterfly effect": small changes in start conditions make the process to go completely different way (while keeping general "average" direction). So any detailed information about military operations would lead to complete change of military situation in battles. And thus any further information becomes completely inadequate. Batlles would happen in new places with different numbers and positions of troops. And thus "suprises" (bad and good) would be completely new.
So "...the best choice is not to play..." - information from future shuold focus on non-military aspects (like "dirty underware" of politics like Churchill), wich would allow Germany to develop in more peaceful way, keeping military actions to local conflicts (sorry, Poland!). But this would lead to unexpected problems with Commis and Japs.
Just hand them the history book
They don't need technical information, access to the 20/20 hindsight that we have available would be enough to change everything, and if they don't take that hint there's no helping them.
There were many mistakes made by all sides in the run up to, and during the war. Given access to that information, advance knowledge of D-Day beaches for example, would make all the difference.
Of course the butterfly effect applies when you start playing that game.
Not really "before WW2 begins" but during the war could reveal things like opponents movements and supplies. If he knew which battles to avoid/write-off, which supply routes were vulnerable, and the advice not to invade Russia could have done a lot to avoid wasting resources and being more effective in dominating.
Also, location of various manufacturing plants, opponent supply lines, and responses would let them use more precise attacks to take out opponents. Again, making sure Japan didn't piss of the US until much later probably would have helped with the world dominating plans.
If you really want to do it before WW2, then start with the nuclear bomb. Now days, it doesn't take much to really create one. If they just had a few more hints on the process and they could have gotten the bombs out faster.
Also, proper encryption techniques. Breaking the ciphers was one of those big things for the Allies, if Germany knew about those or used a more modern suite, that information would have never been compromised.
You would have to assume a rational German leadership that was willing to act on the advice. If there had been such a leadership, wouldn't they have listened to the German advisors who would have argued against two-front wars, declaring war on the United States, and so on? I don't think there are simple one-paragraph pieces of advice that could make Germany win against the US and the Soviet Union.
The Nazis were putting the genocide above winning the war. They were not rational about that.
So a briefing kit with the carrot and the big stick:
- Documentation of the historical outcome of WWII, including the fall of Berlin and the bombing of Hiroshima and Nagasaki.
- A detailed set of plans for Little Boy and Fat Man, and Mark 12, for the Mark 14 and the Mark 27, and plans for the "tools to build tools" like uran centrifuges.
- A set of plans for the V2, Pershing 1, and Polaris with the Ethan Allen-class SSBN.
- Plans for a Mig-17-era fighter and a Phantom-II-era fighter.
Of course this data would be impossible to assemble from open sources. Say several notebook computers with optical media plus a pair of dot-matrix printers (their consumables can be produced in the 30s). The computers alone would be a major boost to the credibility of the time traveler.
The goal would be to make Germany wait several years before it starts the war. Note how the list includes both "immediate" and "stretch" goals. Imagine a late 1940s, with no war yet and Germany a decade ahead of the historical development in a few selected areas. Then they kick off.
If you get to him early enough, have him plan an intelligence operation to assassinate Chamberlain between September 1, 1939 and October 1, 1939.
Although Churchill's later conduct of the war as Prime Minister was admirable, in the winter of 1939-1940 his suggestions as a member of the war cabinet were, in retrospect, insane. Churchill states in his memoir The Second World War in the volume Their Finest Hour that he advocated the following policies:
An invasion of Eire to seize additional Atlantic ports to conduct operations against U-boats.
An invasion of Norway, and then Sweden, in order to cut Germany off from Swedish iron ore.
A declaration of war on the Soviet Union in support of Finland and Soviet-occupied Poland.
Chamberlain stopped #1 from consideration. #2 was actually approved, and extensive planning undertaken; Germany's own invasion of Norway happened before planning could be completed. #3 actually advanced to the joint planning stage with France, but Chamberlain didn't prioritize it.
Had Churchill become Prime Minister earlier - a significant possibility if Chamberlain was killed - his greater energy level and all-around ferocity may have brought one or more of these policies to pass. Any one of them had the potential to lose the war for Britain. All three of them together almost certainly would have lost the war for Britain.
Considering that Hitler was overconfident in his own military expertise the best advice would be:
Let your generals do their job, and stay on the balcony to do the crowd preaching.
A country like Germany, dependent on import for supplies, cannot sustain a long term war. It is forced to proceed with small and temporally short jumps. Cutting off all import supplies with a world war is suicidal in the long term.
This question probably requires you to compile multiple answers, as Germany really had a lot of problems it had to defeat to win the war. From resources to production to tactics and treatment of populations.
You could tell them how the UK will beat Enigma, and then change a lot of codes and how it works. Additionally you could tell them how compromised their spy network was to give them a headstart.
The war would also have lasted a lot longer if the Germans didnt build Tigers and King Tigers, instead focussing on the production of cost effective tanks. Add knowledge early on about sloped armor, rubber synthesis and ballistics of various HE, HEAT, AP and other types of rounds.
Dont throw away lots of resources in things like the V1 and V2 rockets. They packed a punch but had too little accuracy to be useful. On that note any artillery and bombardment campaigns that focused on civilian populace should be avoided. Most of the time it just increases the resolve of the civilian and military populace to fight back as partizans or just holding the line. It is also a massive drain on resources for little gain. Also the Nazi's actually figured out that nuclear weapons wasnt in it for them with their resources so you might tell them in advance.
Teach them about combined arms, mechanized infantry and whats-his-name tactic about breaching lines and then striking supply lines and enveloping the enemy, of which the Blitzkrieg was the accidental precursor. This should massively accelerate many attacks assuming the Germans can produce it all appropriately.
Teach them about war psychology, like instead of firing long lasting artillery barrages you fire 1 salvo every minute. This gives the opposing soldiers time and safety to say "I dont want to be stuck here while death could randomly hit me so I'll just leave", meaning you can capture territory without having to kill many enemies.
Get a reputation for good conduct with captured soldiers. If torture, horrendous labor camps and death await you surrender wont be what you'll do. If reports are that you get treated well then surrendering will be an alluring option to avoid death. War isnt about killing but about making your opponent stop fighting! Naturally because they are Nazi's they could still execute and force labor camp prisoners, just make sure they dont find out until they are far behind the frontlines. Consider that America never even knew the full extent of Auswitz, Sobibor and the like until they actually walked into those camps so the option is there.
And as others already mentioned, tell Hitler that his generals are capable and should do the job instead of him. If you have good personality reports you can also sift out the incompetents, several of which made it into Hitler's inner circle.
It might have been too late in 1939 when a lot of scientists had already left, but it might be very useful to focus on nuclear weapons if you go back a little further.
Germany had the relevant knowledge at the time, and the Manhattan project took just 4 years, so it seems conceivable that Germany could've nuked other countries into surrendering before those countries got nuclear weapons of their own.
It might turn into a really long guerilla war against very angry populations though...
Watch this video, it explains pretty well what went wrong and how you could solve it.
With a time machine it would be relatively easy to give the German side a big advantage. Use the time machine to go back a few years and arrange to have an agent assassinate Churchill. Without the strong leadership provided by Churchill it is likely that a weak and divided British Government would have come to some understanding with Hitler after the fall of France however distasteful that may have been and however unlikely it appears from the modern perspective.
Also ensure that the invasion of Russia went ahead as early in 1941 as possible without the time and material wasting excursion into the Balkans (or the Battle of Britain the previous year). Capture Moscow as the sole primary objective and possibly Stalin as well, if he stayed in Moscow (which might not be the case given the changed circumstances).
Ensure that the Russian people were treated with a lot more respect to enable the formation of a lot more powerful Hiwi units and encourage and make better use of defecting Russian army units under German control. It might have been possible to persuade Hitler that this was necessary as a temporary arrangement to save German lives.
Finally impress the importance of not declaring war on the USA whatever the provocation.
If this is for a story it might also be worth considering some practicalities as well. The time traveller would be going on a hazardous undertaking as nobody would believe they had a time machine on arrival and they probably would not have the correct documentation.
If it was possible to demonstrate the time machine to anyone in authority and they became convinced of its reality, the time traveller might get a special audience with the Fuhrer (and the Gestapo might seize the time machine at this point and then all bets are off).
I'm going to challenge the premise. The best way to win the war is to not start it. Loss was inevitable when they went to tickle the French, the Brits, the Soviets and the Americans, all at the same time.
If German authorities churned German Jews and German Communists into German death camps, that's a German problem. What did the Nazis in wasn't the genocide. We let dictators genocide their own people in feigned indignation. Nobody came to invade Germany from 1933 to 1939 when Nazis trampled on democracy and the rights of the Jews and others. France, UK and allies might be miffed about the "Final Solution" if it went into effect, but let's not forget the Great War was supposed to be the last. They weren't eager to fight a Second Great War.
So convince Hitler to tone it down with the expansionism. Instead of invading other nations, and powerful ones at that, a better play would be to charm the world through diplomacy and soft power. Take a page from China. Export Nazi industry, technology and arts. Strive to make Nazi sports teams the very best in the world. Make trade not war. If they have valuable, tangible trade to offer, maybe we'll call it a misdemeanour against humanity and leave it at that.
Additional to other questions that have made good points:
The Stug III is going to be your most successful armoured vehicle, with the Pz IV coming a close second. Don't bother going after big heavy tanks, it's a waste of resources, and they won't be influential enough to make a difference.
Germany didn't lose because there were important things about how the war was going to go that they didn't know. They lost because the political leadership (Hitler, Goebbels, etc) refused to accept the facts that their rational military experts were telling them.
The German general staff knew fighting on two fronts was a bad idea, Hitler made them do it anyway. The German general staff knew that getting bogged down around Stalingrad was a bad idea, Hitler made them do it anyway. The German general staff knew that if the United States entered the war, they were doomed to defeat, but Hitler didn't care.
At the end of the day, there's no realistic scenario where Germany wins WW2. The only reason they ever thought it was possible was because they (incorrectly) believed that BOTH the Soviet Union AND the United States, the two largest industrial powers in the world, would just roll over and surrender rather than fight.
Remember that from the German perspective, the Eastern Front was the entire point of the war. The Western Front was just a sideshow to knock France and Britain out of commission so they couldn't interfere with the main event, which was taking over the resources and territory in the Ukraine and the Caucasus oil fields.
So, there's nothing you can tell Hitler that's going to keep him from attacking Russia, and there's nothing you can tell Hitler that's going to keep him from fighting a two-front war. And even if somehow he believes you, and even if somehow you can figure out how to attack the Soviet Union without having to fight France, Britain, and the United States at the same time, the Soviet Union could arguably have beaten Germany all by themselves. They had VASTLY more troops, more industrial capacity, and had all the resources they needed, which Germany did not. Without the Western Front it might have taken the Soviets longer to win, but they WOULD have won, and when they did, they would have had control of all of Europe, which at the end of the day was the main reason for the Normandy Invasion.
The Allied invasion of Western Europe wasn't NECESSARY for Germany's defeat. Even if all those troops had been on the Eastern Front, the Soviets still would have won, it just would have taken another year. The Allies invaded to make sure that WHEN Germany lost to the Soviets, the western powers would have military control over all of Western Europe. So the Soviets couldn't take it.
Military information is too specific to influence the whole war. WW2 was not lost in any single battle, and by interfering you change the timeline, so your information quickly becomes outdated.
Advanced technology will be of limited use, unless you get plenty of time before the war to update the whole technology base. During the war material shortages plagued the armament industry.
This leaves changing the political situation. In the west, neither Great Britain nor France were eager for a war with Germany, nor did Nazi policy look for a war there. The leadership of the Soviet Union however considered a war with Nazi Germany inevitable eventually, and the Nazis saw it as inevitable too. Neither of the two nations was in very good standings but reasonably the Nazi leadership could let Stalin make the first step in conquering the eastern European nations between them.
Depending on the situation, Great Britain and France might ally Germany, or even stay neutral. Similarly, the USA would be disinclined to help the Soviet Union. Without the war in the west and the ability to import crucial resources, Nazi Germany stands a much better chance at winning the war.
Discourage development of the Rätte, the Maüs, the V-series rockets (these would eventually become effective weapons, but Germany didn't have the proper technology), and the Bismarck. Seriously, these were major time wasters.
In their place, encourage production of the Sturmgeschutz series. Also, let the guys at R&D finish the Sturmgewher Project, as it will produce the weapon off which two of the three most popular guns of the modern age (the AK-47 and the H&K 33) were based off of.
Tactics wise, here are a few things you could suggest for them to do:
Instead of an air bombardment, go through with Ünternemen Seelow (the plan to invade England). That way, America can't use England as a jump-off point for invasions.
Stay out of Greece and North Africa; there's nothing there that Germany needs, and the British are too strong for the Wehrmacht to win in that area.
Similarly, stay out of Russia for now. Germany is at peace with them, they are staying out of Germany's business, and Germany does not have enough forces to defeat them right now. If they really want to attack them, then suggest that they at least wait a few years so that they can build up sufficient troops.
All this being said, I don't think it would make much of a difference, as the R&D side of things were all pet projects that Hitler pushed through/blocked, and the strategy side is all things where Hitler decided that he was the best strategist who ever lived (he wasn't).