Three of the biggest controversies involving Hip Hop history solved.
1) Is graffiti writing part of hip hop?

Not initially. The first writer may have been Cornbread, who wrote “Cornbread loves Cynthia” in Philadelphia. At first he claimed this was 1967, then later backdated it to 1965 (likely after he discovered Julio 204 had started in 67). By his own account, he had just been released from juvenile detention and was either 12- or 14-years-old depending on which date you accept.
Julio 204’s birthdate has never been released and he stopped tagging in 1970 after being arrested. Julio inspired Greg 69, and Phil T. Greek, who inspired his childhood friend Demetrius to start writing Taki 182 in 1969, when they were both 16-years-old.
But graffiti blasted into the white hot core of hip hop in 1972, when Phase 2 started a chapter of the Ex Vandals at Stevenson High in the South Bronx. A student at Alfred E. Smith Technical also began tagging. He named himself Kook Herc. Both Phase and Herc were 17-years-old.

In 1971, Super Kool 223 had discovered he could replace the nozzle on a spray can with the nozzle from a shaving cream can. This allowed him to create the first masterpiece. Many writers balked because it “took damn near an entire can of paint,” according to Phase. Very quickly, however, the best writers began crafting masterpieces. Phase turned Super Kool’s stick letters into bubbles in 1972, and that led into Wild Style.
The original writers in Washington Heights did not aspire to create masterpieces, replace nozzles, or enter into the art world. There is a profound difference between them and artists like Phase, who easily entered the art world, even though they were marginalized until Keith Haring came along and opened a door for commercializing graffiti.
2) Who was the first rapper?

Coke La Rock began rapping in 1973 at Cindy’s birthday party in the West Bronx when he was 18 years-old. Hollywood began deejaying earlier in 1972, but Hollywood did not rap until two years later, when he was 20-years-old.
3) Who invented breakdancing?
Before it was called “breaking” it was called “going off” and it erupted spontaneously so no one person gets credit. However, Kool Herc immediately recognized having the best dancers was essential to having the best parties, and he cultivated the Twins, Clark Kent, Sasa, Trixie, Eldorado Mike, James Bond, while Coke La Rock made sure to call them out whenever they went off, which made them stars in the emerging culture before the rap crews appeared and took center stage. Herc would reward these displays by extending the break, which was the part reserved for their best moves.
In 1975, in a moment of spontaneous improvisation, Cholly Rock extended the floor spin and finished with a freeze. Sasa had a famous drop, and the Twins did splits like James Brown, and both Kent and the Twins had a spin move, but Cholly laid a foundation for transforming breaking into something entirely new. He was 15 years-old.

Cholly was recruited into the emerging Zulu Kings. After Kool Herc was stabbed and lost his club, Bambaataa captured the center of gravity on hip hop culture, which flourished at Bronx River Projects in the East Bronx. In 1979, the best battles were between the Funky 4 against the Furious Four. In 1983 the best battles were between the Furious Five and the Cold Crush Brothers.
Grandmaster Caz could out-rap and out-deejay most everybody in the Bronx. He had started as a breakdancer, became a deejay named Casanova Fly, and then changed to Grandmaster Caz shortly before joining the Cold Crush Brothers (founded by Tony Tone and Charlie Chase), which happened in 1979, when Caz was 19-years-old.
Hip hop began with blacks in the Bronx, but they were often going off to Puerto-Rican-influenced beats. Many hip hop classics were influenced by those beats, especially “Just Begun” by Jimmy Castor, and “Apache” by the Incredible Bongo Band, which became the ultimate b-boy battle anthem early on when street gang culture was fading and hip hop emerging. Latin teens soon flooded in and re-energized the dance style kicked off by Cholly and the Zulus.

The Beastie Boys switched from hard core to hip hop in 1983, the same year Run/DMC came out of Hollis Queens with a style that brought back an uncompromising style of rap that had been pioneered by Caz and Melle Mel.
The entrance to the Tunnel was obviously a prime spot to hit, and the picture shows Phase2, Herc, Lee 163 and others. The Plaza Tunnel was the only place to be if you were an aspiring b-boy because that is the crucible where b-boy culture was forged.