habitational name from what is now Spain's principal city Madrid. Throughout the Middle Ages it was of only modest size and importance and did not become the capital of Spain until 156 Its name is of uncertain origin most probably a derivative of Late Latin matrix genitive matricis "riverbed" much changed by Arabic mediation (see Madrigal ). There are other smaller places of the same name in the provinces of Burgos and Cantabria and these may also be sources of the surname.