How many men were on the battle front of World War 2?

Answer 1

Well, it depends on how you would define the "battle front". There were 16 million Americans in uniform during the war, but surprisingly few of them were actually doing any fighting. The US had developed an extremely large logistical "tail", which has only grown since then. This is the number of men behind the lines for every one at the front.

If one counts only the infantrymen, the actual foot soldiers, who have to beat the bushes and advance, rifle in hand, looking for the enemy, shockingly few. The US created 91 divisions to fight this world war. The plan had been for 200, but ninety one was all that were made. Of these sixteen were armored divisions, five were airborne, two were cavalry, and one was a mountain division, leaving about 65 infantry divisions. Some of these barely got into the fighting at all, arriving in Europe for only the last few months of the war. An infantry division had close to 15,000 men. But only about 20% were actual riflemen. There were three regiments in a division, three battalions in a regiment. A battalion had three rifle companies, plus a heavy weapons company. A rifle company had three rifle platoons, plus a weapons platoon. A rifle platoon had three rifle squads, plus a weapons squad. Infantry squads were 12 men. So a rifle platoon, at full strength, had 36 riflemen. An infantry company thus had 108 riflemen, and about 80 other guys. It was far, far far more dangerous to be a rifleman than in the weapons platoon - but the weapons platoon guys were sometimes right at the front, and always close to it. So an infantry battalion then had 324 riflemen, out of about 850 total assigned. A regiment then had 972 actual foot soldiers, out of about 3200 in the unit. And a US infantry division then, out of 15,000, had 2916 riflemen, at full strength. Again, the US had only 65 infantry divisions, so if they had all been in action at the same time and at full strength, that's just over 200,000 foot soldiers, for an entire world war. Out of 16 million in uniform. But it was this tiny percentage of US forces that suffered the overwhelming majority of US casualties. In some outfits which were overseas a long time and saw a lot of action (3rd ID, 1st ID, 36th ID, 45th ID) the average rifleman probably had to be replaced at least ten times.

If one counts artillerymen, tankers, combat engineers, mortarmen and machine gunners, and so on, there were quite a few more. But still well under half the number in uniform actually fought for a living.

There were 2 million of the 16 million in uniform who served in the 8th Air Force, engaged in the strategic bombing of Europe. Only a tiny percentage of this 2 million was actual combat crews, of course. But the 8th Air Force had 27,000 men killed for the entire war, out of the 2 million. The 3rd Infantry Division of the army had over 6600 men killed, out of an assigned strength of 15,000, and another 27,000 wounded. 80% or so riflemen. The 1st Infantry Division had over 5100 killed.

There were also six divisions of Marines, all of which fought in the Pacific. They had some heavy losses but their campaigns tended to be relatively short.