Science fiction writers have a sort of fascination with William Shakespeare. (It only stands to reason. Even if they work in a genre which the literary establishment refuses to recognise, they are, after all, writers, and Shakespeare is the paragon of literary excellence in English.) Turtledove, the acknowledged master of alternate history, is no exception to the rule, but, true to form, in Ruled Britannia, he portrays Shakespeare, not as he was, but as he might have been. In this world, the Spanish Armada was successful in invading England, Queen Elizabeth was imprisoned in the Tower of London, and Catholicism was imposed upon the populace by force. Shakespeare, who is more concerned with his dramas than with political reality, just wants to be left alone, but is drawn into a plot to throw off the Spanish yoke.
The dialogue is set in sixteenth-century English, which is a little jarring, but I found myself able to pick it up surprisingly quickly. (For that, I should probably credit growing up on the King James Version of the Bible, and my English 11 teacher, who made us memorise lines from two of Shakespeare's plays. There is a good deal of business about how to tell the religious loyalty of various characters, but it's on what is, for Turtledove, a surprisingly shallow level. There is no real coming to grips with the principles of the Reformation or the Counter-Reformation, either on the Continent or in England. Rather, religion is simply a matter of determining a character's loyalty to the cause. There is a fair amount of discussion of sex, but that is true to Shakespeare's works, which are more ribald than most moderns realise. (There are also a lot of puns in the dialogue, and that, too, is true to Shakespeare. In fact, there are a couple of hilarious scenes in which characters have "quibbles" with one another.)