Question: The Vengeance of Rome (2006) is a novel by Michael Moorcock, in this novel, Colonel Pyat, an incarnation of the Eternal Champion, goes to Italy and Germany, where he becomes involved in Fascism and Naziism, including sexual encounters with which German military officer and an early member of the Nazi Party?

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Elric of Melniboné: Elric of Melniboné is a fictional character created by Michael Moorcock and the protagonist of a series of sword and sorcery stories taking place on an alternate Earth.  The proper name and title of the character is Elric VIII, 428th Emperor of Melniboné.  Later stories by Moorcock marked Elric as a facet of the Eternal Champion.

Pyat Quartet: Pyat Quartet is a tetralogy of novels (1981–2006) by Michael Moorcock comprising "Byzantium Endures", "The Laughter of Carthage", "Jerusalem Commands" and "The Vengeance of Rome".

Warrior on the Edge of Time: Warrior on the Edge of Time is Hawkwind's fifth studio album.  It reached number 13 on the U.K. album charts and was their third and last album to make the U.S. "Billboard" chart, where it peaked at number 150.  Many of the lyrics are by Michael Moorcock and the album is loosely based on the concept of Moorcock's 'Eternal Champion'.  Reviews have been mixed, with "Melody Maker" panning the album and particularly criticizing the vocal work while the All Music Guide has praised the album for features such as the songwriting.

Phoenix in Obsidian: Phoenix in Obsidian (alternate title: "The Silver Warriors") is a science fantasy novel by Michael Moorcock.  First published in 1970, it is the second book in a series that follows the adventures of the Eternal Champion as he is flung from one existence to another.  The first book in the series, "The Eternal Champion", told the story of John Daker, an average 20th-century man who suddenly found himself incarnated as Erekosë, a legendary hero of Earth in the distant past (or distant future).  He had been called to lead humanity against its Eldren foes, but ended up taking the Eldren's side.  "Phoenix in Obsidian" continues the story, which is concluded in "The Dragon in the Sword".  The trilogy is part of a larger cycle about the Eternal Champion as defender of the Multiverse.

Michael Moorcock's Multiverse: Michael Moorcock's Multiverse is an American twelve-issue comic book limited series published in 1997 as a part of the short-lived DC Comics imprint Helix.  It was later collected as a single edition graphic novel.  Written by Michael Moorcock, each monthly issue contained a chapter from three separate storylines featuring distinct groups of characters lifted from Moorcock's sprawling Eternal Champion novels.

The Eternal Champion (novel): The Eternal Champion is a fantasy novel by Michael Moorcock.  First published in 1970, it is based on stories Moorcock published in "Avillion" and "Science Fantasy".  It is the first in a trilogy of books about the Eternal Champion in his incarnation as Erekosë.  The sequels are "Phoenix in Obsidian" (1970), also published as "The Silver Warriors", and "The Dragon in the Sword" (1987).

The Vengeance of Rome: The Vengeance of Rome (2006) is a novel by Michael Moorcock.  It is the fourth in the Pyat Quartet tetralogy.  In this novel, Colonel Pyat, an incarnation of the Eternal Champion, goes to Italy and Germany, where he becomes involved in Fascism and Naziism, including sexual encounters with Ernst Röhm and Adolf Hitler and a sojourn in Dachau.  Mrs Cornelius, the mother of Jerry Cornelius, is another major character.  The end of the novel sees Pyat confronted with his ambiguous heritage and his own unreliability as a narrator.

Jerusalem Commands: Jerusalem Commands is a novel by Michael Moorcock.  It is the third in the Pyat Quartet tetralogy.  This novel takes place between World War One and World War Two, and in it, Colonel Pyat travels from Hollywood to Casablanca, to Alexandria and travels across the Sahara.

Ernst Röhm: Ernst Julius Günther Röhm (] ; 28 November 1887 – 1 July 1934) was a German military officer and an early member of the Nazi Party.  As one of the members of its predecessor, the German Workers' Party, he was a close friend and early ally of Adolf Hitler and a co-founder of the "Sturmabteilung " (SA, "Storm Battalion"), the Nazi Party's militia, and later was its commander.  By 1934, the German Army feared the SA's influence and Hitler had come to see Röhm as a potential rival, so he was executed during the Night of the Long Knives.

Erekosë: Erekosë is a character in author Michael Moorcock's fantasy novel "The Eternal Champion".  He is an incarnation of Moorcock's character the Eternal Champion, and is unique among those incarnations in that he can remember his previous lives, something that frequently causes him great distress.

Supporting paragraphs: The Vengeance of Rome Ernst Röhm
Answer: Ernst Julius Günther Röhm