Every night James Brown went onstage, at some point he would drop to his knees, stare at the ground and ask in his distinctively harsh voice for the audience’s permission to scream. With their encouragement, he would let our out one of the fiercest sounds in the history of pop music, a sound that came to define him as much as the hard-boiled music that swirled around him.

That was just part of the hair-raising theatrical appeal of Brown, who died Christmas morning of conjunctive heart failure in Atlanta. He was 73 and had been hospitalized with pneumonia at Emory Crawford Long Hospital on Sunday, just two days after attending his annual toy giveaway in Augusta.

As a musician and entertainer, Brown was the complete package — a musical innovator, a dancer, a singer, a political activist, a bandleader, a songwriter and a pianist. He was simultaneously a peace-keeper and an agitator. He was thanked and praised by presidents and even struck up a friendship with Hubert Humphrey while he was the nation’s VP, yet he refused, as he wrote in his biography, to do anything that could compromise his commitment to being a strong representative for African-Americans.

“I don’t think he ever got his credit because people saw him just as the show man and not the music innovator and the social innovator that he was,” the Rev. Al Sharpton said upon hearing of Brown’s death. “He changed the perception of regular blacks. He wasn’t tall, light-skinned. He wasn’t polished. He was us. It meant the rest of us could make it.”

Brown came of age at the same time as Elvis Presley, and just as the King did in his early years, Brown indelibly altered the face of American popular music. But unlike Presley, Brown never softened. His music was raw, rugged and rhythmically driven; lyrically he spoke about primal, social and political concerns. He wrote the blueprint for funk and rap, and when sampling of recordings became the modus operandi for hip-hop, Brown’s works were sampled far more often any other.

“He was not only the Godfather of Soul, but the Godfather of Funk and Rap,” Ice Cube said in a statement. “Music will never be the same.”

His nicknames alone have stood the test of time. Godfather of Soul. The hardest working man in show business. Mr. Dynamite. Soul Brother No. 1. His influence was heard in the music of Prince, George Clinton and David Bowie, seen in the dance steps of Michael Jackson and echoed throughout socially conscious rap of the 1980s.

He landed 99 singles into the R&B top 40 between 1956 and 1993; 17 of those records hit No. 1. His 1963 album “Live at the Apollo” spent 66 weeks on the album chart, a record for an R&B disc, and became an icon for all other live albums that would follow.

Brown was in the first class to be inducted into the Rock and Roll Hall of Fame, a recipient of the Lifetime Achievement Grammy in 1992 (he won two others) and his death drew commentary from many corners, including President Bush (“he was an American original”), Mick Jagger (“he was always generous and supportive to me”) and Snoop Dogg (“his legacy will live on through me, in every way you can imagine”).

And proof that his music resonates today with the contempo rock crowd came when the hipster music site Pitchforkmedia.com included four Brown tracks — “It’s a Man’s Man’s Man’s World,” “Papa’s Got a Brand New Bag,” “Night Train” and “Mother Popcorn (You Got to Have a Mother for Me)” — in their recently compiled list of greatest songs of the 1960s.

The facts about his birth and even his name are a bit cloudy, but it is generally accepted that he was born in Barnwell, S.C., on May 3, 1933, as James Joseph Brown Jr. He was abandoned before he started school and reared in Augusta, Ga., bouncing between the homes of relatives and the streets.

His high school years were spent at the Alto Reform School near Tocoa, Ga., where he was sent for breaking into cars. At the school, he met Bobby Byrd, whose family took Brown into their home. Brown and Byrd, a keyboardist, started a gospel group that would eventually become Brown’s backup group, the Flames.

In late 1952 and early ’53, Brown and Byrd performed in and around Tocoa, most often at Bill’s Rendezvous Club. While attempting to come up with a name, they wanted something effective like the moniker of another local group, the Torches. After working as the Flames, a business associate suggested that they improve on the name and add the word Famous. The Famous Flames developed a considerable following in the South. When Little Richard had a hit with “Tutti Frutti” and left the Chitlin Circuit for Los Angeles, the Famous Flames took over Richard’s gigs with Brown as “Little Richard” and Byrd assuming the part of Brown. (On Tuesday, Little Richard told MSNBC that Brown was “an innovator, he was an emancipator, he was an originator.”)

One of the most popular songs of the Flames’ act was a cover of the Orioles’ “Baby Please Don’t Go,” during which Brown would repeat the word “please” over and over and on many a night, they would perform it up to four times. But as the band’s reputation developed, so did national acts’ aversion to having the Famous Flames on their bill, fearing they could be upstaged.

Brown sensed a need to go national to improve their bookings. To that end, they recorded “Please, Please, Please” and started shopping it, but before it was ever purchased or licensed, Macon radio station WBML started playing the track and generating enthusiastic response. The tape made its way to Atlanta, where a talent scout for King Records of Cincinnati fell in love with it. After a gig at a club in Milledgeville, Ga., Brown was signed to King Records.

When King Records honcho Syd Nathan heard the recording, he hated it and would not release it. Despite his reservations, Nathan decided to put it out in March 1956 on the King subsidiary Federal Records. “Please, Please, Please” spent 19 weeks on the R&B chart, peaking at No. 5 and selling a million copies.

Brown would move to King in 1961, recording for the diskery up through 1971. In 1962, he started to cross over with “Night Train,” which went to No. 35 pop/No. 5 R&B, and the follow-ups, “Shout and Shimmy” and “Mashed Potatoes U.S.A.” Brown was doing 300 concerts a year and felt that the recordings weren’t necessarily reflecting his act at its most potent. He needed a live album.

After lobbying Nathan and being refused, Brown financed the recording of his Oct. 24, 1962, show at the Apollo Theater in Harlem; it was the fifth time he headlined the venue and his reputation for delivering some of his finest shows at the venue had preceded him. Nathan went along with the plan, sending a recording engineer to ensure a useable record,

King whittled the recording down to just over 30 minutes, overdubbed applause and pressed 5,000 copies — 500 of them in stereo. Because of its short length, radio stations were asked to play the disc in its entirety. “People were always calling in, asking us to play ‘JamesBrownLiveatTheApollo’ — one word, like it was the name of one of his songs,” said Rocky G, a disc jockey at New York’s WWRL, in the liner notes for Universal Records’ 2004 reissue of the album.

The album caught on, peaking at No. 2 and sitting on the charts for 15 months.

Brown’s career continued to climb, driven by a string of hits between 1965 and 1967 that included “Papa’s Got a Brand New Bag,” “I Got You (I Feel Good),” “It’s a Man’s Man’s Man’s World” and “Cold Sweat.” And while he was selling out basketball arenas, he also honed an upscale nightclub act that was booked at venues such as the Flamingo in Las Vegas. At a July 1967 gig reviewed by Daily Variety, Brown and his 23-piece orchestra wowed the aud with “That’s Life” and “I Wanna Be Around” before turning to “Prisoner of Love.” “This Dr. Jekyll,” Brown told the crowd as he sang standards. “Stand by for Mr. Hyde” (Daily Variety, July 24, 1967).

During the Johnson administration, Brown was ramping up his involvement in political and social causes, working with then-Vice President Hubert Humphrey on a jobs program for blacks and later a stay-in-school program, not to mention becoming one of the first black entertainers to perform for the troops in Vietnam.

At times, he was criticized by more militant black leaders for associating with white leaders — and at times for having white musicians in his band — and for the song “America Is My Home.” Brown didn’t see eye-to-eye with his detractors, countering that he had fought hard to be seen, especially by the black community, as an equal in non-musical activities with whites.

In July 1969, for example, Brown bolted a “James Brown Day” ceremony in Los Angeles when it was clear Mayor Sam Yorty would not be attending. That same year, the FCC investigated and found no problem with Brown explaining on TV his personal take on the difference between black, colored and Negro.

His music in 1968 and ’69 took on an activist stance. “There Was a Time,” “Say It Loud — I’m Black and I’m Proud,” “Soul Pride” and “I Don’t Want Nobody to Give Me Nothing (Open up the Door, I’ll Get It Myself)” signified a seriousness on his part regarding the civil rights movement.

A shining moment occurred in Boston in 1968, a day after Martin Luther King Jr. had been assassinated in Memphis. Brown was scheduled to perform at the Boston Garden and public officials were concerned about crowd safety and the possibility of a riot. Brown, city officials and the concert promoter negotiated throughout the day about the best course of action and as misinformation leaked out, it was apparent they would have problems if the city went through with their first idea to cancel the show.

Brown negotiated to have the concert televised on the local PBS station, which required the altering of another contract for a televised appearance he had just shot in New York. But he also stipulated that he be paid as if the concert were a sell-out, no matter how many people showed up for the Friday show.

Brown performed the concert for about 2,000 people while countless others watched at home. He asked that people stay calm and stay home throughout the weekend and as the show came to a close, he said the entire concert would be immediately re-broadcast, which meant WGBH stayed on the air broadcasting Brown until 2 a.m.

While riots and looting plagued 100 other cities, Boston was peaceful. He would make similar public announcements in Washington, D.C., and Rochester, N.Y., his work generating “thank yous” from President Johnson.

Brown’s records, meanwhile, continued to sell, even ones that were little more than Brown screaming and grunting and repeating words like “popcorn” or “funky.” His music, driven by arranger/band director Pee Wee Ellis, who took over for Nat Jones in early 1967, was becoming increasingly raw and more aggressive than anything coming out of the two hotbeds of soul music, Detroit and Memphis.

But the music business can be a tough one and in 1970 the Famous Flames all ankled at once. The day after they quit, Byrd grabbed a Cincinnati band led by Bootsy and Catfish Collins called the Pacemakers, changed their name to the JB’s and put them on a plane to Columbus, Ga., where they walked onstage and became Brown’s backup band. Although their tenure was short, the JB’s backed Brown on the recordings of “Get Up (I Feel Like Being Like A) Sex Machine,” “Super Bad” and “Soul Power.”

Brown would later allow members of the Flames back into the band, including trombonist and songwriting collaborator Fred Wesley and drummer John “Jabbo” Sparks. He would use the JB’s name, regardless of who was in the band, for years.

As disco dominated black music, Brown, who had created a radio station business and his own production company, disappeared from the charts.

He had a mainstream comeback of sorts in the 1980 pic “The Blues Brothers,” playing a preacher, Rev. Cleophus James. During his song, Brown refused to do his trademark moves or even have his gown removed as he felt it was out of character. His scene, therefore, was dominated by John Belushi’s flips and Brown-inspired moves in the church aisle.

It was “Rocky IV,” however, that truly revitalized Brown’s career. Pic’s theme, “Living in America,” reached No. 4 Pop/No. 10 R&B in 1985 and was ubiquitous on American radio. It led to a deal with Scotti Bros. Records, which yielded his final hits “I’m Real” and “Static” in 1988.

His comeback was cut short after he was arrested for failing to stop for police during a two-state automobile chase that began after he charged into an insurance seminar in Augusta carrying a shotgun. He had some other legal troubles at the time — assault on a police officer, possession of PCP — and he was sentenced to six years.

Brown was paroled in February 1991 and within days he was back in a recording studio. He made his return to public performing on June 10, 1991, at L.A.’s Wiltern Theater, which was also a pay-per-view show.

Brown never eased up on his performing schedule and often changed his band and his standard show. He made a special performance over the summer at the Hollywood Bowl, reprising material he had recorded with the Louie Bellson Big Band in 1970 for the jazz-inspired album “Soul on Top.”

He was scheduled to perform New Year’s Eve at B.B. King Blues Club in Times Square and tonight at the Palace Theater in Waterbury, Conn. The show was to kick off a national tour.

On Tuesday, it became unclear if his marriage to Tomi Rae Hynie was valid. Police said Hynie was married to a Texas man in 2001 when she wed Brown, thus making her marriage to Brown null. Hynie had annulled the previous marriage, but she and Brown never remarried. They have a 5-year-old son.

Brown was married three other times and is survived by at least four children.