Thread by @BO3673

Basket: 1 US Army WW2 Infantry Division.

Estimate Delivery Time: 457 days.

A thread on activating and raising US Army infantry divisions in WW2. (Niche I know...). It all takes longer than you probably think to raise a division in a war at maximum national effort. 1/20

In Dec 1941 there were 10 Regular US Army infantry divisions, 18 National Guard and 1 Army of the US for 29 in total. By 1945 67 infantry divisions would be activated, trained and deployed overseas. 2/20

In 1942 27 infantry divisions were activated. In 1943 another 11 were activated. The 1st to be activated was the 25th division in Oct 1940. The last to be activated was the 65th division in Aug 1943. 3/20

Activating a division and training it wasn't done on the hoof. There existed a clear and well-laid out plan on how to raise a division. This plan was modified in 42 and 43 but remained broadly the same. 4/20

Each new division needed a cadre of officers and enlisted men (EMs) from a parent division. This cadre was 172 officers and 1,190 EMs. The balance of the division would come from "fillers" posted directly to the division. The division would do all training from basic onwards 5/20

The process took 457 days. It started 78 days before "D" day by appointing and giving training to the 172 officers. These officers and the 1,190 EMs arrived at D-30. From D-30 to D day the remaining 452 officers would arrive. The parent division would be backfilled 6/20

From D to D+15 the brand new recruits (13,452) would arrive and the Divisional Training Year would begin. This comprised 17 weeks basic, 13 weeks up to regimental, 14 weeks combined arms and 8 weeks review and sign-off. During training kit was authorised at 50% 7/20

This plan was refined throughout 1942 and 1943. This refinement mainly involved a bigger cadre (216 Officers, 1,460 EMs) and more training and selection and proving of senior officers. At the same time, the Divisional Training Year was shortened 8/20

By the time the last division was activated, 65th division, training had been reduced to 14 weeks individual, 12 weeks regimental and 12 weeks combined arms - 38 weeks in total. This occurred as overseas operations picked up in the ETO and PTO in '43 and '44. 9/20

In part this was because it was felt better for a division to complete a shorter training cycle than be plucked for early overseas service prior to completing a longer cycle. Operational pressures and the need for replacements overseas had a massive impact on training 10/20

Problems included severe training equipment shortages, officer shortages and personnel shortages. For example, the 94th division in 1943 only received 20% of the full rifle-issue necessitating rotating them 11/20

Whilst there were plenty of junior officers, field-grade officers became in short-supply. Divisions were taking much longer to "fill-up" and in 1944 divisions were nearing the end of their training already under strength 12/20

This was being caused by divisions in training, as a matter of policy, being trawled for trained replacements to send overseas as casualties mounted on operations. The numbers involved were deeply disruptive 13/20

Between Apr '44 and Sep '44 17 infantry divisions were earmarked for this practice and lost 78,000 men as individual draft replacements in the middle of their training. Backfilled soldiers then themselves needed to be trained up. 14/20

One of the worst examples was the 100th division which lost 14,878 men to this practice - its entire strength stripped out as it conducted its training. 15/20

So raising a division took a considerable amount of time. The last infantry division to be activated (the 65th) had is CO appointed in May 1943, it activated in Aug 1943 and after its training cycle headed overseas in Dec 1944. 16/20

The result of this was that US Army strength in the ETO had barely begun to get going by D-Day. 13 infantry divisions arrived in France between Jun and Aug 44. 6 more up until October. During the winter/spring of 44/45 20 more arrived. 17/20

Therefore most US infantry divisions arrived after the Battle of Normandy and were still pouring in as the British 2nd Army actually cut 2 infantry divisions from its own strength due to manpower issues in the autumn, adding only one new one (52nd) 18/20

So divisions took a surprisingly long time to raise. Even the US Army had very real issues raising their divisions with operational pressures forcing it to strip men from non-deployed divisions, massively disrupting training with manpower pinchpoints even in the US Army 19/20

The source of this information is the official US Army history (aka the Green Books). None of this is new knowledge, but sometimes its fun to take a deep dive on a logistical aspect of preparing an Army to fight in a war of national survival. history.army.mil/html/books/002… END