It was George Bernard Shaw (or Oscar Wilde, depending on who you ask) who once said that “England and America are two countries separated by a common language.” This may be true enough even among Americans. Our regional accents are the result of more than two centuries of settlement and immigration, where the primary influences were of one people or another from the "old country," whichever country that was for them, and in whichever part of America they settled.
If we want someone else to repeat something we didn't quite make out, we would say "Come again?" or "I'm sorry?" or "Say what???" In the southwestern part of Ohio where I grew up, along the edge of the "German triangle" (the corners more or less being Saint Louis, Chicago, and Cincinnati), the response of "Bitte?" became "Please?" I don't believe I ever heard it anywhere else. I lost that quirk of speech within a few years of moving to DC. Saying "eye-ther" instead of "eee-ther," and/or "nye-ther" instead of "nee-ther" took a bit longer. I still remember when I was but a little “schnickelfritz” (a term of endearment that somewhat literally translates as "mischievous boy," but is equivalent to "little rascal") and hearing some of my Dad's aunts or uncles speaking with a slight guttural sound to their voice. This would have been common to the French accent as spoken by their grandparents, who mostly came from the Rhineland region of Alsace-Lorraine. When I addressed him, I'd call him "Dad" with a slight "y" tone to the vowel, to sound just a little like "Dayud," whereas my East-Coast-born-and-bred son just calls me plain old "Dad" (when he isn't accidentally calling me "Dude").
Even now, whenever I return to "Cincinnatuh," I start speaking like a native within a couple of days. And yet, even in an era of constant migration, where the suburban flight has peaked, and people are moving back into the cities (as in an article and illustration from Business Insider), New Englanders still speak of having to "pahk the ka" before going into the store. And way down South, they still make "shoo-fly pie" and say "y'all," except in urbane, sophisticated oases like Atlanta.
What a country! Let's hope we can still get along without screwing things up.