What's the history on this 1928D series $2 bill?

You'll probably need a copy of a US paper money guidebook to get exact dates. Otherwise, information is scattered piecemeal on the Web. I was able to find that the Series 1928B $2 notes are considered the 'key' to the 8-note 1928 series, and that they were printed between February 1932 and March 1933. The Secretary Treasurer and Treasurer pairings seem to be the main factor in changes to the next edition - when an office changed hands, notes with the next pairing were printed as the next letter of the same date. Only when a note underwent a major design change did a new date appear - Series 1928 ran from 1929 until the Series 1953 notes were printed (probably in 1953 when the newly-elected Eisenhower appointed new office holders).

Series 1928 notes are dated 1928, or 1928 A thru G. From looking at who the office holders were, it looks like both Morgenthau and Julian appeared om Series C and D, so the switch to D probably occurred for another change to the note.

Ordinarily, it wouldn't be too hard to give you some solid info--I use http://www.uspapermoney.info/serials/ for a lot of currency questions, and if it were a Series 1974 or later bill, I could even tell you what month it was produced.

Unfortunately, data on older notes is much harder to come by, and the BEP wasn't as good about being "neat" with production dates--plates from a couple of different series might be in use at the same time. But, there are a couple of things we can do to help narrow down the dates a little. This is gonna get long, but hang with me.

The first is the signature combination. Julian and Morgenthau were in office together from Jan 1934 through July 1945. While there is usually some delay between people taking office and the notes with their signatures appearing, I have no clue what it was in this case--but it's typically only a few months. On the $2 bills, their signatures appeared on both the '28C and '28D notes. The difference between them is...

The size of the plate number on the front (yeah, I'm underwhelmed, too). They went from a very small size to the size we use today. Because the backs are printed separately, they have different plates, and it's not uncommon to find '28D notes that were printed with the "old", small number back plates. On your note, the "258" on the front is the front plate number, and the "311" is the back plate. If the back plate number is very small, you've got what's called a "mule" note. Because they're common, it's not worth more than a non-mule, but it's still an interesting piece of trivia.

From here on, it's largely speculation--the value of this info is roughly what you paid for it...

To try to narrow the date down more, the same plate number change happened with $1 bills, causing them to go from Series 1935 to 1935A, so it's reasonable to assume that the earliest it could have happened would have been about 1936, but I strongly suspect it was quite a bit later than that.

There were about twice as many 28D notes as 28C's. If we guess that they were printed at about a constant rate, the change from 28C to 28D happened roughly 3 1/2 years after their terms began in 1934, so given the "lead time" to get a new series ready, I'd estimate the start of 28D production at about January 1938.

Now, let's throw another layer of supposition on top of that. The website I mentioned also tracks serial number ranges. The lowest serial 28D he shows is B 83988001 A, and the highest is D 29712000 A (once the serial number reached B 99999999 A, the next would have been C 00000001 A). By a stroke of luck, your note falls almost exactly in the middle.

So if the printing was constant, and '28D production ran from January 1938 through about October 1945, your bill would have been produced about in the middle of that time, which would be roughly the fall of 1941.

The last bit of technical info concerns the "K" next to the face plate number (BTW, there should also be one in the top left corner). Notes are printed on large sheets, and then cut into individual bills. The sheets have 32 bills now, but back when yours was printed, the sheets contained 12 notes (2 across and 6 down). To show where a note was originally on a sheet, they added a "plate position" marker. The 12 subject sheets were arranged like this:

A G

B H

C I

D J

E K

F L

so your note was originally on the right side of the sheet, one up from the bottom.