3 PEOPLE WHO COULD HAVE HELD THE TITLE BEFORE MIHAWK
The greatest swordsmen before Mihawk !!
Dracule Mihawk is currently the greatest swordsmen in One Piece but when Roger was executed Mihawk was only a rookie so during his rookie days who was the strongest swordsmen?
Shanks was also a rookie so Shanks could not have been the greatest swordsmen.
So we only have 3 people worthy of this title:
Gold Lion Shiki
Shiki was a great swordsmen in the series this is because he was seen with 2 katanas on top of a pile of marine soldiers until Garp and Sengoku arrived.
Eventhough he lost against that duel with Sengoku and Garp he destroyed half of Marineford with 2 swords.
I think that he got weaker after he cut his legs and replaced them with his katana.
Shiki also has a devilfruit to back his power he could float anting he touches meaning that if get the slightest cut from Shiki you would have lost.
Dracule Mihawk vs Gold Lion Shiki
Inorder to beat Shiki Mihawk could have hunted him down to challenge him to a duel to become the greatest swordsmen.
So in this battle Mihawk won the duel after beating Shiki to get his title from him.
Ryuma “The King”
After his death the legendary samurai was buried in the land of Wano.
He was known for slaying a dragon and the hero of wano meaning the he could possibly have been the greatest swordsmen before losing his life to Mihawk.
He was a samurai with immense physical strength durability and speed but he could have been weaker in his zombie form meaning that Zoro was only able to beat a fracture of his real strength but he would be a lot stronger if he was human.
It could be possible that Mihawk killed him inorder to become the greatest swordsmen.
He could have lost to Mihawk in his final battle and he could also have lost his life during that battle and later he was resurrected.
“Dark King” Silvers Rayleigh
He in my personal opinion was the previous holder of the title but he isn’t that dependent on his sword he usually uses haki to escape or avoid fights.
He was seen dueling with Kizaru at level terms with swords and he could have faught Mihawk sometime after Roger’s death losing his title to Mihawk
Mihawk was his last ever duel and he intentionally gave the title to him because Mihawk had more determination of being a swordsmen rather than Shanks even though both of them were equally skilled in swordsmenship.
If I’m correct Mihawk saw the same determination in Zoro when he first met him meaning that Mihawk found his successor like Rayleigh did when he met Mihawk.
But he could also have gotten the title from these other 2 swordsmen.
*Theory by King of beasts kaido