The world’s biggest country, in a magazine. Since 1956.
So, what do we know about Sogdia and the Sogdians, the relentless holdouts against Arab dominion? Not as much as, say, the Persians, but there is a place to start.
Begin by reading the nice Wikipedia entry about Sogdia. Includes maps, loads of outlinks and lots more information than you can absorb in a single sitting.
Certainly you can absorb this in a 48-minute sitting. It's an episode from the 1980s documentary series The Silk Road, "The Soghdian Merchants":
You may also want to read a bit about An Lushan, a Sogdian who rebelled against the Tang Dynasty. (It may prove useful when it comes time to read the second book in the trilogy...)
Finally, check out this nice exhibit of Sogdian art, hosted by Washington University.