The English constitution has been an object of admiration and has been taken as an example to imitate, for many centuries and throughout the world. This phenomenon raises many questions. Here are some of them. Why was it a model, despite its difficult reconstruction, not being contained in a single text and being for some parts founded on customs? Why does it inspire so different norms? What strength derives from the constitution and what impulse, on the contrary, arises from those systems that took it as a model? What does the long history of transplants of the English constitution and its principles teach to historians and legal scholars?