''Sometimes I fear this war will end up making Gryffindors out of all of us!'' Achilles Greengrass - 1942
Minister for Magic:
Leonard Spencer-Moon (Phoenix, Hufflepuff, Half-Blood) (1)
Head of the Department of International Magical Cooperation: Lord Achilles Greengrass (Sphinx, Slytherin, Pureblood) (2) (3)
Head of Department of Magical Law Enforcement: Lord Caratacus Crouch (Sphinx, Huffelpuff, Pureblood) (2) (4)
Coordinator in-chief of the British Battle Wizards on the Continent:
Theseus Scamander (Phoenix, Gryffindor, Half-Blood)
Senior Undersecretary to the Minister of Magic: Amata Fortescue (Owl, Ravenclaw, Pureblood)
Head of the Department of Magical Accidents and Catastrophes:
Torquil Travers (War Dragon, Ravenclaw, Pureblood) (5)
Head of the Department of Muggle Liaison: Hasting Virecker (Pheonix, Gryffindor, Muggleborn) (6)
Chief Warlock of the Wizengamot: Arabella Bones (Pheonix, Gryffindor, Half-Blood) (7)
Head of the Departament for the Regulation and Control of Magical Creature: Cormoran Beauclair (Owl, Slytherin, Half-Blood)
Head of the Goblin Laison Office: David Goldstein (Lion, Ravenclaw, Pureblood)
Head of the Centaur Liaison Office: Anastasia Constantinov (Owl, Huffelpuff, Half-blood)
British Representative at the International Wizarding Confederacy: Augustus McLaghen (Sphinx, Gryffindor, Pureblood) (8)
Head of the British Division of Magical Trading Standart Body: Porphiria Selwin (War Dragon, Ravenclaw, Pureblood) (9)
Head of the Department of Misteries:
Henry Potter (Phoenix, Gryffindor, Pureblood)
Unspeakable-in-Chief: Travis Jones (Sphinx, Gryffindor, Muggleborn)
Head of the Department of Magical Transportation:
Wilhelmina Tuft (Sphinx, Huffelpuff, Half-Blood)
Head of the Department of Magical Sports: Borros Digory (Phoenix, Huffelpuff, Half-Blood)
Chief of the Auror Bureau: Antonia Abbot (Phoenix, Huffelpuff, Pureblood)
Head of the Department of Education: Balthazar MacMillan (Sphinx, Huffelpuff, Pureblood)
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Other Canon Figures of Political Importance Collaborating with the Ministry in one way or another:
(I gave the american characters the faction they most likely would have in Wizarding Britain while the muggles get RL political affiliations that would have made sense for them in the time and context).
Newton Scamander (Lion, Huffelpuff, Half-Blood): Still acting as Dumbledore active hand in Europe, Newt has more or less accepted that, for the time being, his fame will come from his actions in the war rather then as a maziologist. He, his brother and their in-laws have proven to be such a torn on Grindelwald side that the sheer mention of the name ''Scamander'' in his presence his enough to make the most terrible dark wizard since Herpo the Fool throw a tantrum of spectacular proportion.
Porpentina Scamander (Thunderbird, Half-Blood, Lion): She has yet to recover from Quennie's defection to Grindelwald and plunged body and soul into the fight to cope. The American Valkyrie, as the legendary american auror is now known, is presently leading the forces of the International Wizarding Confederation supporting the lawfull italian ministry against the pro-Grindelwald rebels.
Seraphina Picquery (Horned Serpent, Pureblood, Lion): After leaving her post she was consumed by guilt over Grindelwald escape, tough most didn't hold it against her. To atone for what she saw as her mistakes she toured the world and meet with influent wizards to convince them of the danger represented by Grindelwald. She played a key role in putting toguether the massive coalition presently fighting him.
Col. Jacob Kowalski (A randow NY city public school, Muggle, New Deal Democrat (10)): To the eyes of the muggle world Jacob Kowalski is nothing more then one of the many officers dwelling in the corridor of the White House in these years of war. The truth, however, is far less banal: While it as accepted to modify the Rappaport Law to make him an exception to many of its requirements the MAVUSA still reluctant to establish direct contact with its muggle counterparts, despite the repeated demand of the latter. Thus, when Newt doesn't require his help for one of his mission, Jacob essentially act as Special Presidential Adviser for Magical Affairs. In the spite of the very real pain he still feel at the memory of Queenie's decision he cannot help but feel some pride at how far he has gone.
Winston Churchill (Sandhurst, Muggle, Moderate Tory): The possibility of ties between Grindelwald and Nazi Germany as well as his friendship with Spencer-Moon has lead Churchill to exhibit a degree of knowledge on and interest for magical affairs quite unusual among muggle prime minister. Regularly briefed by the ministry, Churchill has met many of its key figures and even the purists among them have taken to refer to him as the ''The First Muggle'' with something sounding suspiciously like respect.
Nobby Leach (Ravenclaw, Muggleborn, Phoenix): Put in Ravenclaw solely because of the fact that shorting a muggleborn in Slytherin during this era would have been against his interests, Leach quickly proved to be an immensely talented and driven wizard who, while often the target of purist bullying, made a point of honour to give more then he got. After a few years working as an unspeakable he headed to Europe to fight the good fight and ended up forming an elite band of wizards operating in areas supposedly controled by Grindelwald, with devastating effect for the latter. He and his battle wizards have come to be nicknamed The Boguarts for their seeming tendency to manifest in whatever way Gellert could have most feared.
Percival Graves (Thunderbird, Pureblood, Phoenix): Driven by the desire to ensure that he would be remember as more then a kidnapee, Graves has been instrumental to the creation and management of the system designated to train and organise wizarding volounters coming from all accross the world and ensure that they are quickly ready to face Grindelwald hordes.
(1) Once a simple tea boy Spencer-Moon ascended among the ranks and, thanks to his seat at the Wizengamot, spent much of the 1930's attempting to convince Wizarding Britain of the sheer gravity of the threat represented by Grindelwald and of the necessity of decisive actions to counter it. As such, he seemed to many the natural choice to lead the Rainbow Ministry.
(2) I was a bit conflicted when it came to nobility titles as, on one hand, I do admit allot of fanfics run with it far beyond the reasonable and cannonically wizards don't have a landed nobility. On the other hand, Lord Voldemort name, wizarding manors and the whole ''Most Noble and Ancient House of Black'' do show that the trapings, if nothing else, of aristocracy. I decided to cut the apple in two and have particularly prestigious and families bear courtesy titles who, while empty of any actual legal meanings, do testify of their social ranks. More in a latter worldbuilding piece.
(3) The leading figures of the owls turned sphinxes because of the Global Wizarding War, Achilles Greengras played a key role in the deposition of his former friend and political companion Hector Fawley as well as the formation of the political coalition presently leading the ministry. The de facto number two of the ministry, Greengrass has been given the reins of the Department of International Wizarding Cooperation, a post of crucial importance in the circumstances. Father of Hercules and Ulysses and uncle in-law of Tiberius McLaghen.
(4) Cora Crouch father.
(5) The former Head of the Department of Magical Law Enforcement lost much in the fall of minister Fawley but he proved influential enough to retain a seat at the table. Close to the Blacks he allow them to retain some influence over the minister, even if only indirectly. The father of Sullivan Travers, he grown estranged from his son due to their political differences, tough he still use his influence to protect him from some of the consequences of his opposition to the war.
(6) Due to the twin emergencies of WWII and the Global Wizarding War the Muggle Liaison Office was temporarely elevated to the rank of a full department. Hasting Verecker got the job due to his connection inside the muggle world, who the ministry hoped would serve them well, being a relative of
John Vereker, 6th Viscount Gort.
(7) In many way a logical candidate for the post of Head of the Department of Magical Law Enforcement but political realities forced Spencer-Moon to give the job to a Sphinx. She was made Chief Warlock to provide her with a consolation price. Aunt of Patricia Bones
(8) While certainly competent, he obtained the job thanks to the patronage of his brother in-law, Achilles Greengrass. Father of Tiberius and uncle in-law of Hercules and Ulysses.
(9) Your second cousin, once removed. The tensions between the two branches of the Selwin familly have prevented the potential connection she represent to be of much use to you.
(10) As a catholic immigrant with a working class background Jacob would have most likely been a supporter of FDR.