The legend of Nostradamus emerged during his lifetime in response to the accuracy of some of his predictions. Like all gifted psychics, he was able to read other minds and, based on a dollop of common sense, prognosticate somewhat into the future. He had some hits, which always get the press, where his misses have not been carried down through history. Over time the legend of Nostradamus swelled, as the retelling of his hits were repeated but the list of misses slipped from memory. Thus, he appears larger in death than he was in real life. Nostradamus is credited with future predictions in part due to the semblance of famous names with words in his quatrains, but the quatrains mentioned could have fit literally thousands of situations and the names were not a direct fit. The Nostradamus quatrains could have an unlimited interpretation, and thus the pieces of the puzzle have been put together to paint many different pictures. They are 100% subject to interpretation.
Nostradamus knew well the power of suggestion, and used this during his lifetime to increase the number of his hits. His amusement at this capacity outlived him, as one of his most famous practical jokes was to predict, on his deathbed, that his body would be exhumed, naming the date. He directed that a metal plate with this date be placed in his coffin, and not surprisingly events resulted in his coffin being opened on that date. Those who knew of this date kept alive the discussion of whether his coffin would be opened, so that the issue did not die.
It is reported that Nostradamus wrote his quatrains in an obscure manner to avoid detection and punishment during his lifetime. In fact, he wrote in this obscure manner to avoid being fingered when he missed the mark. People would interpret his quatrain correctly, as applying to their present day, and when Nostradamus' predictions came true there were smiles all around. However, if the prediction did not come true, Nostradamus would mumble darkly that the interpretation made had been wrong, and let people come to their own conclusions. Thus all manner of conjecture has arisen surrounding Nostradamus, that he has a secret code imbedded in his quatrains which make sense of the garble, for instance. There is no such code, nor were his quatrains intended for any but his day, but since Nostradamus fans are having such a good time dissecting his quatrains and arguing amongst themselves, we suspect our words here will be mostly ignored.