Because of its location, Spain has been subject to many external influences, often simultaneously, since prehistoric times. At times the country itself has been an important source of influence to other regions. Archaeological and genetic evidence strongly suggests that the Iberian Peninsula acted as one of three major refugia from which northern Europe was repopulated following the end of the last ice age. It has also played an important part in Europe and even the world at certain historic times; in the latter case when it was the seat of a global empire that has left a legacy of 400 million Spanish speakers today.