Well, no. There have been several religions that predate Christianity that have resurrection stories. Early Christians tried to destroy the stories of earlier religions. Resurrection stories were once pretty common.

Oh not even close to original on that, just as many other things

It would be fair to say that the RC version is the most risible.

OTHER GODS THAT ROSE FROM THE DEAD IN SPRING BEFORE JESUS CHRIST
Posted on December 8, 2016 by Garrett S. Griffin under Religion
In the same way many ancient Mediterranean societies told tales of gods born to virgins (some on December 25) before the time of Christ, the archetype of gods rising from the dead is likewise older than Christianity, an uncomfortable historical fact for many religious people but not necessarily unforeseeable given the power of human imagination and the long stretch of human history before the Common Era (or Anno Domini, A.D., if you prefer).

In human religion, gods often die and return to life, sometimes in their old form, sometimes in a new one (see All About Adam and Eve, Richard Gillooly, and Godless, Dan Barker). They also often came to earth disguised as mortals, especially in Greek and Hindu myths.

Dionysus was killed, descended into hell, and was reborn — in Zeus’ thigh of all places. Greek gods, goddesses, and mortals often descended into hell for various reasons and later rejoined the living. Demeter’s daughter, Persephone, descended into Hades and returned in the spring.

Attis, a Phrygian-Greek vegetation god born of the virgin Nana, castrated himself and, depending on the version, either bled to death from this or was hanged on a pine tree. He was reborn after three days, his blood redeeming the earth as it fell from his body. His worshipers celebrated the salvation from death offered to them by Attis by decorating a pine tree each spring.

This took place on March 25, a date later used by Christians for the Easter celebration (while no longer used for Easter, Catholics still use it to celebrate the Feast of Annunciation of the Blessed Virgin Mary).

In Egypt, Osiris died, was resurrected, and ascended into heaven. Horus came back from the dead. Like many gods related to vegetation, Adonis, worshiped in Babylonia and Syria as early as the 7th century B.C., died annually (in the fall) and was resurrected (in the spring). In Greece, Heracles was mortal but rose into heaven to take his place among the gods just before he died.

In Hindu mythology, Shiva cut off Ganesha’s head but Pavarti convinced him to bring the god back to life. Krishna is accidentally killed by a hunter, but comes back to life and ascends into heaven. The Sumerian king Tammuz was killed but resurrected by the gods and made a god himself. According to the Mesoamerican people, Quetzalcoatl killed himself, but after a few days in the underworld returned to heaven.

Then there’s Mithra, made the “Protector of the Empire” by the Romans in 307 AD, right before Christianity was declared the official religion, but actually a Person god worshipped before 200 B.C. Some versions of Mithra’s story make him the son of a human virgin. His birth, on December 25, was seen by shepherds and Magi, who brought gifts to a cave, the place of his birth. He performed miracles like raising the dead and healing the sick and blind; he had 12 disciples, representing the zodiac; he died, was put in a tomb, and ascended into heaven; the spring equinox was when worshipers celebrated his ascension. Believers predicted that in the Last Days, the battle between good and evil would consume the earth. The righteous would be saved, the wicked would go to hell (see Barker).

Just as the winter solstice inspired the celebration of the birth of many gods and demi-gods in the northern hemisphere, the spring equinox saw feasts for countless deities around the world. Some cultures in the Middle East made it the start of their new year. During the two days of the spring equinox, day and night are the same length. The Council of Nicaea in 325 decided Christ’s resurrection would be celebrated on the first Sunday after the first full moon after (or on) the spring equinox.

Norse religion: There is evidence that the Norse believed in reincarnation where one's hugr would pass into the body of a newborn relative while one's hamingja continued on in the family at large and one's fylgja seems to have just ceased to exist at the person's death.

And Scientology...

No.

No. Christianity borrowed the idea from several earlier mythologies.

Mankind has always believed in some form of resurrection. This is a basic belief because we cannot accept that we will no longer exist at some point. We do not want our thoughts or ourselves to perish.