Decades before the twirling, hip-shaking grooves of salsa music exploded into a global phenomenon, it emerged from the glitzy New York mambo clubs in the 1940s and 1950s and made its way to the streets of Spanish Harlem.

New York City in the ’40s and ‘50s was the perfect breeding ground. A new, African-based Cuban music was melding into the city’s vibrant big band jazz scene. And a huge wave of Puerto Ricans moving to New York—nearly 900,000 between the mid-‘40s and mid-‘60s—were, as the decades passed, claiming a new identity in their new home, fueling a fresh, hard-pounding music with their own distinctive voice.

“Salsa provided a rhythm and music that we could live by, breathe and make love to,” Latin music promoter and publisher Izzy Sanabria explained in the documentary TV series “Latin Music USA.” “It was the essence of the Latino soul.”

Salsa evolved from mambo, which itself had origins in son, an up-tempo urban folk music from eastern Cuba that evolved as it made its way to Havana and then to the clubs and streets of New York City. Mambo’s most popular early ambassadors in New York were Machito and his Afro-Cubans, a band that hit the city’s music scene in the 1940s and revolutionized mambo.

Mario Bauzá, the band’s Cuban-born founder and musical director, had been drawn to the freedom and energy of Harlem. After settling there in the 1930s, he was soon playing trumpet and arranging tunes for big band jazz ensembles under leaders like Chick Webb and Cab Calloway.

He later recruited his brother-in-law, Francisco Gutiérrez Grillo, to be Machito, the singer and front man of the new band with the unique Latin sound.

That sound, says longtime musician and educator Bobby Sanabria, was the first time a big band used a trio of drums from Cuba to drive an Afro-Cuban beat: the bongos created by creoles; the timbales derived from the timpani (or kettle drums) in Europe; and the congas, a newcomer to popular music with the most direct connection to West Africa’s rhythms and culture.

And long before it became culturally popular to embrace African roots, the band’s name purposely made a point. “I’m of African descent. And the rhythms that produces the music we play is African,” Bauzá explained in “Latin Music USA.” “You ever hear the expression lemon meringue pie? That’s exactly what this is. Jazz in the top and the Afro-Cuban rhythm at the bottom.”

His band was the headline act in 1947 at the inaugural Latin night at The Palladium Ballroom, located on the Lower East Side of Manhattan, which would soon be hailed as "the home of the mambo." Police closed streets around the club to handle hundreds of fans, many dancing in line while waiting to get in.

Transit workers, bank executives, seamstresses and professionals—all dressed to the nines—shattered racial, ethnic and class barriers as they moved their hips to pulsating drums and blasting trumpets. The well-known rivalry among the big three featured bands—led respectively by Machito, handsome crooner Tito Rodriguez and timbales virtuoso and showman Tito Puente—pushed mambo’s cultural currency in the city to new heights.

The Palladium became a spot for the “in crowd” to be seen. After curtain calls on Broadway’s Wednesday matinees, celebrities came to party. Sammy Davis Jr. sat in on bongos. Marlon Brando got high marks for his licks on a conga. Jazz trumpeter and bandleader Dizzy Gillespie, who later fused the African-based sound to some of his own Bebop jazz, showed up with singer Sarah Vaughn. Dean Martin, Rita Hayworth, Kim Novak were also in the mix—among other stars. According to one of the club’s professional dancers, Pedro “Cuban Pete” Aguilar, Ava Gardner would come in and pick men to dance with her. “I had the privilege of dancing one number with Elizabeth Taylor,” he shared in The Palladium: Where Mambo Was King.

The Palladium closed in 1966. Other clubs kept the music alive for a time, but the mambo craze waned. Meanwhile, a new generation of Puerto Rican migrants to New York, dubbed Nuyoricans, were awakening to a new sense of pride, affirming their own identity and civil rights during the turbulent 1960s and ’70s.

They did it, in part, through music that would be labeled salsa. Cuban music was the core of the salsa style, ethnomusicologist Peter Manuel states, but the music “became reborn as a symbol of Newyorican (sic), and by extension, pan-Latino ethnic identity.”

Trombonist Willie Colón and salsa/jazz pianist Eddie Palmieri brought trombones to the front of their bands for a deeper, harsher, more aggressive sound Palmieri called “the roar of elephants.” That roar was heard everywhere on the streets, spilling out of apartments, barber shops and corner bodegas in Spanish Harlem, known as El Barrio, and the Lower East Side neighborhood nicknamed Loisaida.

Some hard-driving tunes yearned for nostalgia from home, Puerto Rico, where scores of other bands also brought their music to a growing international salsa scene. On pavement and tar streets in festivals, crowds in New York grooved to blaring horns and honest lyrics recounting their hard lives among the city’s working class.

Much of those hard-pounding beats were produced by salsa powerhouse Fania Records. Dominican musician and bandleader Johnny Pacheco started the label in 1964 by selling vinyl records out of the trunk of his Mercedes. His partner, Italian American lawyer and ex-cop Jerry Masucci, borrowed $2,500 from his mother to launch the record label that internationalized the Latin music coming out of New York.

Fania’s big salsa stars like Ray Barreto, Larry Harlow, Cheo Feliciano, Bobby Valentin, Hector Lavoe and Celia Cruz produced their own recordings. But Pacheco assembled most of them into a supergroup dubbed the Fania All-Stars for epic concerts that crisscrossed North America and beyond. After packing Manhattan’s Cheetah Club to more than double its capacity in August 1971 (and later releasing two live LPs from the blowout event), the All-Stars caught fire, bringing 40,000 salsa fans to Yankee Stadium in 1973 and playing to 80,000 in a stadium in Zaire a year later.

Ironically, it was toward the final days of Fania that the record label released in 1978 what’s considered the best-selling and most influential salsa album in history, Siembra (Planting). Colón and Panamanian salsa singer and composer Rubén Blades came together with an unconventional sound to detail the sadness of urban life in tunes like “Pedro Navaja” or, as in “Plástico,” to urge people to shun the fake consumerism of the disco days and to wake up to real truths of their lives and their people.

Salsa has gone through slower pop- and ballad-infused variations as decades passed. But for many, it’s always been about the basics. For Palmieri, whose hits “Puerto Rico” and “Adoración” are emblematic of the hits now known as la salsa vieja (the old salsa) or la salsa dura (the hard salsa), what keeps fans around the world moving their feet, and what keeps people emotionally and culturally connected over time, is the rhythm and the beat.

When Bauzá brought the trio of drums into the mix, the innovative Cuban bandleader had the right idea, said Palmieri in The Palladium: When Mambo Was King.

“The drum, which imitates the pulse of life, is the essence of our music,” he said.