1st Infantry Division (Wehrmacht)
The 1st Infantry Division () was an infantry division that notably served in World War II as part of the Heer of Nazi Germany's Wehrmacht. It had been one of the original infantry divisions of the Reichswehr. Operational history

Before World War II 
The staff of the 1st Infantry Division was initially assembled under the cover name of Artillery Leader 1 () in October 1934. Its initial headquarters were at Königsberg. On 15 October 1935, the formation was redesignated as the 1st Infantry Division. It was redeployed to Insterburg on 3 February 1936. The division initially contained the Infantry Regiments 1 (Königsberg), 22 (Gumbinnen), and 43 (Insterburg), as well as Artillery Regiment 1 (Königsberg). The division was built from the Reichswehr-era 1st Infantry Regiment, assembled largely from East Prussian personnel and adopted a strongly Prussian internal culture, as underlined by the black-and-white divisional insignia. The divisional commander from 1 October 1934 until 1 October 1935 was Georg von Küchler, who later went on to be the army-level commanding general that the 1st Infantry Division served under starting in September 1939. Küchler was replaced as divisional commander by Walther Schroth on 1 October 1935, who was in turn replaced by Joachim von Kortzfleisch on 1 January 1938. On 17 August 1939, the 1st Infantry Division initiated mobilization procedures as part of the German preparations for the Invasion of Poland. World War II

Invasion of Poland 

With the German Invasion of Poland in September 1939, the 1st Infantry Division fought in the northern sector. The division advanced toward Warsaw as a component of the XXVI Army Corps (until 1 October 1939: "Army Corps Wodrig", commanded by Albert Wodrig), subordinate to the 3rd Army (Georg von Küchler). The division's commanding general was Joachim von Kortzfleisch, while the chief of staff and head of logistics were Major Johannes Steffler and Captain Christian Müller. On 1 September 1939, it captured Kuklin on the left flank of the 3rd Army. It engaged Polish forces near the heavily defended town of Mława (Battle of Mława) for several days, then crossed over the Bug and Narew Rivers. On 8 September 1939, 1st and 12th Infantry Divisions captured the Ostrów Mazowiecka region. On September 10, the 1st and 12th Infantry Divisions formed a bridgehead south of Brok and Małkinia Górna. On the 12th, the 1st Infantry Division reached the road between Kałuszyn and Siedlce, where it was engaged by Polish counterattacks on its left flank. On 16 September, Wodrig Corps met heavy resistance from scattered Polish formations; the nearby 12th Infantry Division secured the Kałuszyn-Latowicz area, whereas 1st Infantry Division itself was assigned to the area east of Garwolin. The strategic balance of the German campaign in Poland was decisively altered by the Soviet invasion of Poland that started on 17 September 1939; the 1st Infantry Division was subsequently deployed to the Stanisławów area, with 12th Infantry Division assigned further south in Mińsk Mazowiecki, with both division participating in the Siege of Warsaw. Two days later, 1st Infantry Division advanced to Łochów. Battle of France 
Philipp Kleffel assumed command of the 1st Infantry Division on 15 April 1940, and returned to command again on 4 September after a brief interruption by Friedrich Altrichter that had begun on 12 July 1941. Having played only a minor role in the invasion of France, the division returned to East Prussia in the autumn of 1940. Eastern Front 
With the launch of Operation Barbarossa, the 1st Infantry Division participated in the Baltic Operation as part of the 18th Army with Army Group North, advancing on Leningrad. Following a directive by OKH on 15 October 1942, every single infantry regiment in the German army was redesignated as a "Grenadier Regiment", although regiments who claimed the tradition of specific Imperial German Army or Reichswehr units could also petition for their redesignation as "Fusilier Regiment" or "Rifle Regiment". In the case of the 1st Infantry Division, this resulted in the Grenadier Regiments 1 and 43 as well as the Fusilier Regiment 22. The 1st Infantry Division remained and fought in the area of Leningrad and Lake Ladoga through December 1943, as part of the German operations during the Siege of Leningrad. Transferred to the 1st Panzer Army, the division fought at Krivoy Rog and broke out of an encirclement in March 1944. Defence of East Prussia 

The 1st Infantry Division returned to its native East Prussia in the summer 1944. In September 1944, the division received reinforcements to restore its regiments' third battalions, bringing the division up to a strength of ten battalions. Except for participating in the urgent and temporary link-up with the now-isolated Army Group North in Lithuania (Operation Doppelkopf), the unit remained to defend the easternmost German province from the advancing Red Army. On 1 October 1944, Hans Schittnig assumed divisional command. Alternating between 3rd Panzer and 4th Armies, the division was trapped in the Königsberg/Samland area after it was cut off from the rest of Germany by end January 1945. At 0400 hours on 19 February 1945, elements of the 1st Infantry, led by a captured Soviet T-34 tank, spearheaded a westward offensive from Königsberg intended to link with General Hans Gollnick's XXVIII Corps, which held parts of the Samland peninsula, including the vital port of Pillau. Capturing the town of Metgethen, the unit opened the way for the 5th Panzer Division to join with Gollnick's forces near the town of Gross Heydekrug the next day. This action re-opened the land route from Königsberg to Pillau, allowing for the evacuation of civilian refugees via the port and solidifying the German defense of the area until April. Henning von Thadden assumed divisional command on 28 February 1945. With the capitulation of Königsberg on 9 April 1945, the surviving elements of the division retreated to Pillau where most later surrendered to the Soviets and parts of the division where evacuated by sea and surrendered to the British in Schleswig-Holstein at the end of the war. The final divisional commander was a colonel-ranked officer named Egon Overbeck, who assumed the post on 26 April 1945, after Henning von Thadden had been wounded in action. Organization

Subordinate formations 
Initially, the 1st Infantry Division consisted of the Infantry Regiments 1 (Königsberg), 22 (Gumbinnen) and 43 (Insterburg), as well as Artillery Regiment 1 (Königsberg) and the Division Units 1 for support. Each of the infantry regiment was equipped with three battalions and the artillery regiment with three detachments. By November 1944, this scheme had been only superficially changed; the Infantry Regiments 1 and 43 were now called "Grenadier Regiments", whereas Infantry Regiment 22 was now called "Fusilier Regiment". Additionally, the division had received the Division Fusilier Battalion 1 and Artillery Regiment 1 had been strengthened with the addition of I./37 detachment. Superior formations

Commanders
The following officers commanded the 1st Infantry Division:
 1 October 1934 – 1 April 1935: Georg von Küchler
 1 April 1935 – 31 December 1937: Walther Schroth
 1 January 1938 – 14 April 1940: Joachim von Kortzfleisch
 14 April 1940 – 12 July 1941: Philipp Kleffel
 12 July – 4 September 1941: Friedrich Altrichter
 4 September 1941 – 16 January 1942: Philipp Kleffel
 16 January 1942 – 30 June 1943: Martin Grase
 1 July 1943 – 10 May 1944: Ernst-Anton von Krosigk
 10 May 1944 – 8 June 1944: Hans-Joachim Baurmeister
 8 June 1944 – 30 September 1944: Ernst-Anton von Krosigk
 1 October 1944 – 28 February 1945: Hans Schittnig
 28 February 1945 – 26 April 1945: Henning von Thadden
 after 26 April 1945: Egon Overbeck

Insignia 
Inspired by its strong geographic and cultural ties with Prussia, the 1st Infantry Division adopted the coat of arms of the House of Hohenzollern, a black-and-white quartered shield, as its divisional insignia. Sources

References

Literature
 Christopher Duffy. Red Storm on the Reich: The Soviet March on Germany, 1945. New York: Atheneum, 1991. pp 164,165,207 
 Samuel W. Mitcham: Crumbling Empire: The German Defeat in the East, 1944. Westport: Praeger, 2001. pp 66,141 
 Burkhard Müller-Hillebrand: Das Heer 1933–1945. Entwicklung des organisatorischen Aufbaues. Vol.III: Der Zweifrontenkrieg. Das Heer vom Beginn des Feldzuges gegen die Sowjetunion bis zum Kriegsende. Mittler: Frankfurt am Main 1969, p. 285. Georg Tessin: Verbände und Truppen der  deutschen Wehrmacht und Waffen-SS im Zweiten Weltkrieg, 1939 – 1945. Vol. II: Die Landstreitkräfte 1 – 5. Mittler: Frankfurt am Main 1966. 0*001
Military units and formations established in 1934
1934 establishments in Germany
Military units and formations disestablished in 1945

de:1. Division (Militär)#Infanterie-Verbände