With the start of World War I, Höcker deployed with his regiment to the Western Front, first seeing action in the Battle of Liège. He was promoted to Oberleutnant on 5 October 1916 and served as a company commander and acting battalion commander. He was taken prisoner by the French on 23 October 1917 and remained a Prisoner of war until 18 February 1920.[1][2]
Upon Höcker's return to Germany, he was assigned to Reichswehr-Infanterie-Regiment 14 of the preliminary Reichswehr and subsequently assigned to the Reichswehr's 18. Infanterie-Regiment. In 1922, he received a seniority date as Oberleutnant of 5 October 1916. He was promoted to Hauptmann on 1 February 1924 and Major on 1 October 1933.[1]
On 1 April 1934, Höcker was transferred to the staff of the Infantry School and on 1 January 1935, he was on the staff of the War School (Kriegsschule) in Munich. He was promoted to Oberstleutnant on 1 April 1936. In the years leading up to the start of World War II, he served as a battalion commander in Infanterie-Regiment 116 and Infanterie-Regiment 88 and on the staff of the War School in Hannover. He was promoted to Oberst on 1 January 1939.[1]
With the mobilization for World War II, Höcker was given command of the newly-formed Infanterie-Regiment 487. On 19 January 1942, he was tasked with the leadership of the 258th Infantry Division and with his promotion to Generalmajor on 1 April 1942, he was named commander of the division. On 1 January 1943, he was promoted to Generalleutnant. Höcker was transferred to the Führerreserve (Leaders Reserve) on 1 October 1943, and named commander of the 17th Luftwaffe Field Division on 5 November 1943. He was named commander of the newly formed 167th Volksgrenadier Division on 17 October 1944.[1] On 10 April 1945, he was named commander of the 167th Infantry Division (a reorganization of the remnants of his existing command), and on 17 April 1945, of the remnants of the 59th Infantry Division.[3]
Höcker was in Allied captivity from April 1945 to June 1947. He died on 10 August 1961 in Detmold.[4]
Fellgiebel, Walther-Peer (2000) [First published 1986]. Die Träger des Ritterkreuzes des Eisernen Kreuzes 1939–1945 — Die Inhaber der höchsten Auszeichnung des Zweiten Weltkrieges aller Wehrmachtteile [The Bearers of the Knight's Cross of the Iron Cross 1939–1945 — The Owners of the Highest Award of the Second World War of all Wehrmacht Branches] (in German). Friedberg, Germany: Podzun-Pallas. ISBN978-3-7909-0284-6.
Scherzer, Veit (2007). Ritterkreuzträger 1939–1945. Die Inhaber des Eisernen Kreuzes von Heer, Luftwaffe, Kriegsmarine, Waffen-SS, Volkssturm sowie mit Deutschland verbündete Streitkräfte nach den Unterlagen des Bundesarchivs, 2. Auflage [Knight's Cross Recipients 1939-1945. The Holders of the Iron Cross of the Army, Luftwaffe, Navy, Waffen-SS, Volksturm and Germany's Allies, According to the Documentation of the Federal Archives, 2nd Edition] (in German). Ranis/Jena, Germany: Scherzers Militaer-Verlag. ISBN978-3-938845-17-2.
