Central Command is an organisation mentioned in Wolfenstein (2009) as the ruling structure of the Third Reich (or current "New Reich"/Fourth Reich), and mainly situated in Berlin (approximately 1945).
There are some confusing details about the Central Command such as the implication that Wilhelm Strasse is one of the individuals in charge along with Heinrich Himmler. Although Wilhelm Strasse may hide the fact that he is one of the biggest individuals pulling strings in the weakened Reich (weakened by Hitler's major defeat at the Reichstag bunker during Operation Eisenfaust or at Castle Wolfenstein, see Original Encounter). No one appears to mention Hitler, but rather only reference to the mysterious Central Command.
Strasse was both in charge of Operation Nachtsonne and Ubermensch and Zetta was his subordinate, but many did not know he was actually the one in charge, and believed he was transferred over to Isenstadt following Zetta's death. Yet, many documents indicate that Strasse had been involved with the Natchsonne project since its inception, and maintained his secret leadership from the castle there. As such there are some strangely contradictory mentions of Central Command or at least a section of it existing inside Isenstadt Castle under Strasse's control. There are no pictures of Hitler in his castle, and only an ostentatious painting of Strasse himself (although this may just be an indication that he sees himself as the Third Reich's greatest leader in his own ego). Seemingly the individual who wrote those Central Command reports appear to defer himself to Strasse, and again there is never any mention of Hitler issuing any commands (though Hitler may appear in the Graphic Novel, as the individual 2nd from the right).
Behind the scenes
According to iD software at the time that Wolfenstein (2009) was being developed the game was seen as a sequel to RTCW, which was also a sequel to Wolfenstein 3D. This was reflected in the animated graphics novels for Wolfenstien 2009 as well, as well as some of the published material for RTCW including the strategy guide. There are nods made within the game to Spear of Destiny and other missions B.J. has been on where he's been seen as tall and blond (like in the original game). However, Tides of War and possibly Wolfenstein 3D Classic treat RTCW as a prequel to Wolfensten 3D.
However, it is possible that very little of Wolfenstein (2009) was utilized as part of plot of Wolfenstein: The New Order. "...we asked him if the last Activision Wolfenstein game had any baring on their version to which he replied, "No it does not. We try not to include that game as part of our story. Personally, I think that Activision did a crap job." In fact the designers claimed to be more of a fan of the original game in the series instead (Wolfenstein 3D).
No firm date is given for when the game takes place, but at least one trailer and the animated series suggest that its 'after the war', meaning after WWII. However, some of the dates given in the game may suggest anywhere from late 1944 to 1945. There are perhaps a couple of references to 1945 (but the text is unclear).
When Gamespot asked if Mecha-Hitler would be in Wolfenstein: The New Order, they were told that he was already defeated in Wolfenstein 3D (but still possibly alive). It was suggested to them that a version of events of Wolfenstein 3D are part of the reboots canon. This may have been hinted at in the Nightmare, based on hazy memories B.J. is able to have in the Kreissau HQ. In a newspaper (List of Newspapers (The OId Blood) ) in the Old Blood it does make a reference to B.j.'s assassination attempt on Hitler,mans that Hitler survived and recovered from the attack. Hitler claimed that B.J.'s escape and his death were vicious rumors. But then again the newspapers themselves may also be just propaganda, and B.J. was more successful than is actually stated.