No, they are not the same person - or rather, deity in Greek myth.
Chiron, the centaur son of Cronus and Philyra was half brother of Hades, Hera, Zeus, Hestia, Poseidon, and Demeter whose mother is Rhea and father is also Cronus.
Dionysus is the son of Zeus and (usually) Semele.
No.
Chiron was apparently called by the same name by Roman's.
Christians do not.
Endeis, a daughter of Chiron, who was married to Aeacus, by whom she became the mother of Peleus and Telamon. Melanippe/Euippe, who was the mother of the god of winds Aeolus. Ocyrhoe/Ocyroe, who revealed the secretes of the gods - is also called Melanippe. Carystus, the son of Chiron, who became the father of Aristaios, foster-father of Dionysus.
Chiron tells Percy that Mr. D is a god. Mr. D is the camp director and Dionysus the god of wine. He also says that almost every city in America has a building that represents the gods. This is some evidence he uses.
Because Thalia's tree was poisoned and someone had to take the blame. Obviously, Dionysus would not take responsibility for it so, it ended with Chiron being 'fired' and was replaced (temporarily with Tantalus)
It's Chiron.
i am pretty sure that Chiron is a godess
chiron's rivals are titans, and Ares
Chiron did not have a 'last name'.
He can make a person go mad and he can bring back a person from the underworld.
There is Grover, Clarisse, Annabeth and Percy(of course), Luke, bits of Kronos, Tyson(Percy's Half-Brother), Dionysus, Chiron, Thalia, Polyphemus, The Golden Fleece, Tantalus, The Party Ponies, Rainbow the Hippocampus