The Standard American accent, as we recognize it today, evolved from a blend of British influences following the colonization of North America in the 17th century. When the first permanent English settlement was established in Jamestown, Virginia, in 1607, diverse regional dialects from England coexisted, mixing over time. However, it's unclear exactly when this distinct "American" sound emerged or when it began to diverge noticeably from British English.

The Standard American accent, often referred to as the "newscaster" or "Network English," is considered the most neutral American English accent. It lacks strong regional, ethnic, or socioeconomic markers, making it ideal for broadcast media. Unlike regional American accents, it doesn't trace back to any specific part of the U.S. but became a mainstream form of communication, especially after the War of Independence and the westward expansion of the U.S. in the 18th and 19th centuries.

With increased immigration during this period, new sounds entered the American vernacular. The blending of various ethnic groups—such as German, African, and Mexican immigrants—contributed to the shaping of a more unified "American English." By the mid-18th century, this Americanized version of English began to take shape.

By the time of the 1790 census, 20% of the nation's population spoke languages other than English, further influencing American English. German-speaking immigrants, for instance, brought clipped speech patterns that became embedded in the General American accent, while African slaves contributed significantly to the development of African-American Vernacular English (AAVE). Immigrants from Mexico, Eastern Europe, and other regions continued to enrich the language, adding unique words and phrases to the American lexicon.

Examples of Loanwords in American English:

• Mexican Spanish: Ranch, guerrilla, plaza, rodeo, guacamole, Nevada, Arizona

• German: Kindergarten, waltz, doppelgänger

• Greek: Anonymous, democracy, metropolis

• French: Entrepreneur, café, rendezvous

• Yiddish: Bagel, klutz, nosh

• Native American Languages: Skunk, moose, raccoon, and names like Mississippi, Michigan, and Chicago

The British-American colonists, encountering new plants, animals, and landscapes, adopted numerous words from Native American languages as well, further shaping the language that would evolve into Standard American English.

In summary, the Standard American accent is a unique product of centuries of cultural and linguistic exchange, with contributions from the British, Native Americans, European immigrants, and enslaved Africans. This linguistic melting pot has given us a rich, diverse language that continues to evolve today.