After the defeat of Big Mom, Blackbeard, Shanks, and the Worst Generation, Akira recruited Big Mom's massive army, the crews of the Worst Generation, and half of both Blackbeard and Shank's crews, the other halves going to Riku Di Cielo of the Demon-Eye Pirates. The Whitebeard Pirates later joined Akira after the rise of the Goshin, with their division commanders becoming Great Dragon Pirate division commanders. CP9 members Jabra, Kaku, and even Rob Lucci joined as the assassination divisions. After Riku took out the Shichibukai, Akira recruited Boa Hancock, former Shichibukais Sir Crocodile & Gecko Moria, as well as their crew mates, and the Donquixote Family, who all became divison commanders. After the recruitments, the Great Dragon Pirates grew from 8 members to over 1,000,000 members, including Baron Tamago, Mr. Pekoms, Diamante, Trebol, Pica, Urouge, Jewelry Bonney, X Drake, Basil Hawkins, Killer, and Shanks (each being a division commander). Big Mom, Eustass Kid, Capone Bege, and Scratchmen Apoo were the only ones who refused to join, only because they didn't want to be under someone elses control. Instead, Akira handed them over to the Navy. Blackbeard was never given the option of joining, due to his traitorous ways, and was personally executed by Akira.
Each member were close friends as kids and met up after the death of Monkey D. Luffy. They then joined Akira and became the Great Dragon Pirates. Although Yoshitoki has reptilian-like abilities, he never ate a devil fruit. He had the traits of certain reptiles surgically implanted in his body by Navy scientists so that they could create a human who had the abilities of a Zoan-type Devil Fruit eater and could still swim. The crew is each given a codename based on their rank of skill. After the defeat of the Yonko, Akira officially made each of the other core crew members division commanders, similar to Whitebeard.
"Shinji of the Mirage" (ミラージュのシンジ, Mirāju no Shinji)
Division Commander Rankings
This a list of the Commanders of the Great Dragon Pirates in order of rank. Commanders 19-21 and 29-39 were the Whitebeard pirate division commanders. They were each given a new division number based on their strength. Each division contains about 120,000 pirates, excluding the commander, with the Main Division being an exception, having about 200,000.