This pedigree has been made by one of my grandfather's brothers, my father has said, but he couldn't remember which one.
Dad thought that the primary reason for this at the time (the late 1930ies) was to show to the national socialists, who were coming into power, that there had been no "unwanted", that is, jewish, marriage in the past of the family.
So, if anyone cares enough to verfiy the whole thing, feel free to do so.
Also, it does not mention earlier incidents where our family name popped up in sources outside of Tirol, namely a document "Ursprung des Regensburgischen Hansgrafen-Amtes" (Origin of the Hansgrafen-Amt in Regensburg), which names one Richero de Marchperg as attending a day of court in mid-11th century, among other notables (this is a clear indication that Richero was a person of some political weight, probably a ministeriale, or lower noble. More research would be necessary).
Then there is a mentioning in the book of vassals of the styrian branch of house Lichtenstein, where a Marchperger is named as having a manor/farm south of Stainach Irdning, where indeed there is a Marbergerweg leading up the "Gatschberg" (verbally: "Mud-Mountain") from 1248.
And there are a number of other occasions where the name pops up pre-15th century, which are not solvable via Google at this point of time, so digging through Archives in those matters should get results, if anyone had the time :)
Also notable: In the book of tyrolean nobility the family is not entered with the signet shown here, but a different one (Mom has got the page, have to get it, and make a picture).
There we're noted as Barons, in the original usually "Freiherr", which would fit the positions of various family members in military and government (as it was).
More details would obviously be welcome.
But to the predigree: It's focused on the Tyrolean Branch, missing out on the German one (where one very notable Marberger wrote an important book on mercantilism.. I'll link the title later), and of course the Americans.
And it ends with my great-grandfather's generation, so to my best knowledge noone has personal memory of any of the people on the pedigree, only stories.
I'll do my best to add the information as I find it, but as already mentioned, in a section for registered family members.
That is to say: Many members of this, well, tribe, do very cool stuff. Would be cool to keep track of each other.