See Thor's Various Incarnations Over The Years

Thor, the Asgardian god of thunder, first appeared in Marvel comics in 1962 in Journey into Mystery #83.

In 1966, the series Journey into Mystery where Thor originally debuted was retitled to The Mighty Thor, giving the hero his own eponymous comic.

In 1983, Beta Ray Bill, an alien from the Korbonite race was deemed worthy to lift Mjolnir, thus granting him the powers of Thor. He would later return the hammer to the Thunder God and was granted the mystical hammer Stormbreaker by Odin as a reward.

In 1988, an architect by the name of Eric Masterson wielded the mantle of Thor for several years while the Asgardian god was banished by Odin for having supposedly slain Loki. When Thor is finally released from his banishment, Masterson is rewarded with an enchanted mace which he continued to use under the alias of Thunderstrike.

In 1986, Thor was turned into a frog by Loki, but he could still wield his hammer Mjolnir. He then proceeded to lead the frogs of Central Park in a successful campaign to defeat dastardly rats.

In 1987, an alternate future Thor from the year 2587 named Dargo Ktor was deemed worthy to wield Mjolnir and gain the powers of Thor. He would transform into an avatar of Thor to defeat Loki and his minions.

On October 1, for the first time ever, a woman shall be deemed worthy to wield the hammer Mjolnir and possess the powers of Thor.