The Library of America is currently running through James Thurber pieces for their "story of the week" feature, and last week's was his "If Grant Had Been Drinking at Appomattox."
The introduction notes that this was a parody of a series of alternate-history articles that had been running in Scribner's Magazine in 1930, and which was quickly brought to a close with its third item after Thurber published his parody in The New Yorker. The implication is that Thurber embarrassed the series, whose items the intro claims were "quickly forgotten," into silence.
What the intro doesn't tell you is that all three items, plus eleven others, were published the next year, 1931, in book form, as If It Had Happened Otherwise, edited by J.C. Squire. Rather than being forgotten, this collection became a classic of alternate history. I have a copy of the 1972 reprint edition, which is available used, though since it runs about $200 a copy, it looks like time for another reprint.
The implication is that the "forgotten" essays are dull and pompous, but they're anything but. "If Booth had Missed Lincoln," which is by Milton Waldman (best remembered now as the editor to whom J.R.R. Tolkien sent a long explication of his mythology in 1950 when Waldman was trying to wrest the works away from Tolkien's previous publisher), takes the form of a review of an imaginary biography of Lincoln, and focuses on the peace-minded Lincoln having a postwar standoff with the Radical Republicans in Congress - which I agree would probably have happened, if not quite so gruesomely or with the tragic ending depicted here.
"If Lee Had Not Won the Battle of Gettysburg" by Winston Churchill (yes, the Winston Churchill), is a goofy attempt to write an alternate-history from the alternate-history's point of view, trying to imagine our history. Churchill quickly drops American affairs and turns to British politics, claiming that a Confederate victory in the war would have led to Gladstone and Disraeli exchanging parties, with the severe Gladstone reverting to his Tory origins and Disraeli leading the Radicals, and an end result of the squashing of the breakout of World War I. In contrast to the Waldman, I'm not sure I believe any of this, but it's an amusing notion.
"If Napoleon Had Escaped to America," by the noted historian H.A.L. Fisher, is written as a memoir by Napoleon's U.S. aide-de-camp, who follows the Emperor in his attempt to establish a new empire in South America. Like Waldman's Lincoln, the story terminates abruptly, but it's an amusing conceit.
Of the other eleven essays, only a couple, like Churchill's, deal with the all-too-common turning point of the losing of a war, and some are a bit imaginative, like "If Louis XVI had had an Atom of Firmness" (by André Maurois) or "If the General Strike [in the UK in 1926] had Succeeded," a rather nasty imaginary newspaper (set in newsprint type) by Ronald Knox. Most of the authors are notable: G.K. Chesterton and Hilaire Belloc, Philip Guedalla and Emil Ludwig. I won't go through them all, but I will point to my favorite: it's by the editor, John Squire, and it's the furthest removed from political history: "If It Had Been Discovered in 1930 that Bacon Really Did Write Shakespeare," which treats popular culture reaction to the news ("What does it matter who wrote such romantic and reactionary rubbish?" - Mr. G. Bernard Shaw), and is altogether to my taste the funniest piece of alternate-history I've ever read. Even funnier than Thurber's.