I thought this is interesting about mexican Spanish as quoted by wikipedia:
“Mexican Spanish (Spanish: español mexicano) is a version of the Spanish language, as spoken in Mexico and in various places of Canada and the United States of America, where there are communities of Mexican origin.
Spanish was brought to Mexico beginning in the 16th century CE. As a result of Mexico City’s central role in the colonial administration of New Spain, the population of the city included relatively large numbers of speakers from Spain. Mexico City (Tenochtitlan) had also been the capital of the Aztec Empire, and many speakers of the Aztec language Nahuatl continued to live there and in the surrounding region, outnumbering the Spanish-speakers for several generations. Consequently, Mexico City tended historically to exercise a standardizing effect over the entire central region of the country, more or less, evolving into a distinctive dialect of Spanish which incorporated a significant number of hispanicized Nahuatl words. Nowadays, the manner of speaking of the people of the State of Mexico influences the way people speak in the central region of the country.”