The Legal Foundation of Downton Abbey, Explained

Now that Downton Abbey withdrawal is beginning to set in, it's time for those of us who suffered through Property I and II to nail down exactly what is preventing first-born Mary Crawley from claiming title to the Earl of Grantham's estate or at least staking claim to her American mother's fortune. The obstacle to inheriting Downton Abbey, of course, is a severe form of our old feudal friend primogeniture, which gives title in descent to the oldest son. Some forms of primogeniture allow succession to daughters, but not, apparently, in the case of Downton, which is entailed to a male heir. Without the entail, Mary would inherit and upon marriage Downton would become the property of her husband and so pass out of the control of the Crawleys, clearly a catastrophe if one is more devoted to a historical genealogical tradition than to one's flesh-and-blood children. So what about her mother's fortune?  How did that become beyond the reach of Mary and her sisters? According to a wonderfully snarky review, "The Abbey That Jumped the Shark," in the New York Review of Books, the answer is that mother Cora's money has been "contractually incorporated into the comital entail in perpetuity," endowing both title and estate exclusively to male heirs. (SBM Blog can't swear that this analysis is right, but NYRB prides itself on getting such things right.) So there you have it. Will Season 3 bring us any legal intrigue related to the entail, or will the focus turn to the peculiarities of the English criminal law in the 1920s, as the forces of good try to spring the long-suffering batman Bates from prison?