DOO-DAH!, by Ken Emerson, Simon and Schuster, 1997, $30.

When did popular music in the United States begin? According to Ken Emerson, author of the new book “Doo-Dah!”, pop music in America was born on Sept. 11, 1847, the day Stephen Foster’s song “Oh! Susanna” was first performed in public.

As Emerson writes, “No popular song is more deeply rooted in American consciousness than `Oh! Susanna.’ Everyone knows it, and yet, the more closely one considers it, the clearer it becomes that we scarcely know it at all.”

One of the many wonderful things about Emerson’s book is that he helps us to see more clearly Foster’s great songs and how American popular music developed.

Ken Emerson will be speaking about “Doo-Dah! Stephen Foster and the Rise of American Popular Culture,” for the benefit of the Hancock Point Chapel at 8 tonight at the chapel. Admission is $5.

“Stephen Foster is at the heart of the tangled, tortuous interchange between whites and blacks that both dishonors America and yet distinguishes its culture worldwide,” Emerson says in his introduction. “Foster is so absorbed in the air that we breathe and in the airs that we hum, in our blood and in our assumptions, that we seldom if ever think of him. Yet an America without Foster is as unthinkable as an America without Whitman or Twain, without Louis Armstrong or George Gershwin, without rock ‘n’ roll, without racism — or without those instances of amazing grace when, if only for an instant, we transcend that racism.”

Since Ken Emerson has been a music critic, especially of rock music, for 25 years or so, he has an encyclopedic knowledge which allows him to compare Foster’s music and that of his 19th century contemporaries with the works of such varied composers as Charles Ives, Irving Berlin, Dimitri Tiomkin, Bob Dylan and Elton John.

The themes from Foster’s songs, such as “Old Folks at Home,” “Swanee River” and “Old Black Joe,” appear in various arrangements and for various reasons throughout American musical history. As Emerson says, “Foster’s music has cropped up in recent movies as disparate as `Natural Born Killers’ and `Little Women,’ and in 1994, `My Old Kentucky Home, Goodnight!’ was featured in television commercials peddling Toyota Camrys manufactured — where else? — in Kentucky.”

Foster was born in Pittsburgh on July 4, 1826, the same day John Adams and Thomas Jefferson died. Even though Pittsburgh is described as “Smoke City,” a rough and rude place choked with coal dust, pianos were being manufactured there by 1813.

“… the pump was being primed for original, indigenous popular music … all that remained was to put sheet music in the parlor — a home delivery system that was expedited by innovations in transportation, communications, and printing,” Emerson writes. “The canal, the steamboat, the railroad, the telegraph, the high-speed rotary steam press, the paper-cutting machine, color lithography, new ways to convert rags into paper — all these forces converged in Stephen Foster’s childhood to revolutionize Jacksonian America and make popular culture in general, pop music in particular, possible.”

Foster is described as being “…shy and unsociable, withdrawing either to his room or to the woods.” He makes his debut as a composer at the age of 14 with “The Tioga Waltz.” His father said, “… his leisure hours are all devoted to musick, for which he posseses a strange talent.”

In 1850, Foster married Jane McDowell, but the marriage was stormy. He never made much money, and he died alone at the age of 37, a penniless drunkard on the Bowery in New York City.

As Emerson sums it up: “Stephen Foster the first great popular songwriter. He took African-American influences, Italian opera, German art songs. He took Irish and folk songs, and he synthesized those in music as multicultural as America itself. … Foster blazed the trail that eventually led to Tin Pan Alley … Stephen Foster’s music … seems to be all the things to all people — from the crowd at Churchill Downs on Kentucky Derby Day to a lone Caribbean immigrant riding the New York subway — and it has been so for a century and a half.”

In a recent telephone interview, Emerson, who has summered on Hancock Point since he was 12, said the years spent researching and writing “Doo-Dah!” helped him make sense of his own “incoherent life.”

“It was an idea that occurred to me five or six years ago, and it enabled me to put together all the disparate strains of my life: popular music, history, American and British literature, and my background of growing up in the Ohio River Valley. I feel that the Ohio River Valley is an underappreciated factor in American history and culture. I don’t think it’s coincidence that the person who first synthesized American music lived and grew up in the geographical region that essentially united America.”

The book’s title, “Doo-Dah!,” which comes from Foster’s “Camptown Races” song, “may well have been a hooker’s come-on,” according to Emerson. After all, horse racing in Pennslvania was illegal then.

Peppered with amusing and insightful quotations from the likes of Charles Dickens and Anthony Trollope’s mother (who chronicled the frequent spitting habits of Americans), Emerson’s fine book is crammed with colorful characters like Dan Rice, a multitalented entertainer who may have given us the model for Uncle Sam, and Martin Delaney, a brillant black leader of the time who deserves his own biography.

Emerson quotes George Gershwin as saying, “The rhythms of American music are more or less brittle; they should be made to snap, and at times to crackle.”

His paean to Stephen Foster and American popular music snaps and crackles all the way through.