The young Diana was pretty straightforward, at first. She first appeared in flashback in Wonder Woman #23 (1947), but did not reappear for some time. She was used by Robert Kanigher again starting in Wonder Woman #105 (1959), at firs
Wonder Girl is a heroine notorious for a convoluted, ever-changing history due to a lack of editorial coordination and several line-wide reboots. There've been three Wonder Girls so far, all related to Wonder Woman: a young Diana, Donna Troy and Cassie Sandsmark. The confusing bits mostly concern the first two. A related character, Fury, was a sort-of Wonder Girl for Earth-Two.
The young Diana was pretty straightforward, at first. She first appeared in flashback in Wonder Woman #23 (1947), but did not reappear for some time. She was used by Robert Kanigher again starting in Wonder Woman #105 (1959), at first as a back-up feature. Unlike many other superheroes, Wonder Woman did not have a sidekick, so Kanigher chose an approach similar to Superman. Soon, Superboy and Superbaby found their counterparts in Wonder Girl and Wonder Tot. And all was well, for a year or two. Then, things got weird, starting in Wonder Woman #124.
Dubbed "the Impossible Stories", by some sort of Amazon magic, Wonder Tot, Wonder Girl and Wonder Woman are able to exist at the same time and have adventures together. Not just them; teenage versions of Manno and Wingo as well. Only one Steve Trevor, though. This runs until Wonder Woman #158, where Kanigher invites them all to his office to get rid of them. These stories would decades later be identified as taking place on Earth-124.1.
In July, 1965, Bob Haney creates the Teen Titans in collaboration with Bruno Premiani. Unaware of Wonder Girl's identity, Haney has her join the team and treats her as her own separate character, marking Donna Troy's first appearance. Generally referred to as Wonder Chick, W.G. and other hip appellations, she would not get a name or origin until Teen Titans #22. She was rescued from a fire at age 2 by Wonder Woman and brought to the island as noone knew who she was. After learning this, the Titans set up a new identity for her, Donna Troy, so she can fully live in the US. Marv Wolfman and George Perez later expanded the backstory, detailing what happened before the fire.
Crisis on Infinite Earths messes things up. In 1987 Wonder Woman is rebooted by George Perez. In the new reality, Wonder Woman was never Wonder Tot or Wonder Girl, was only in her twenties and she didn't leave Themyscira before the formation of the Teen Titans. Donna Troy, on the other hand, starred in DC's best selling title, New Teen Titans (Volume 1), so she couldn't just disappear.
A new origin was needed for Donna Troy, so in 1988 Wolfman and Perez come up with the Who Is Wonder Girl? storyline. This is basically the same except that it is Rhea, not Wonder Woman, who saves her. She is a "Titan Seed" now. From that point on, Donna would constantly change codenames, identities and origins.
Comes 1996, and John Byrne creates a new Wonder Girl, Cassandra Sandsmark, daughter of Wonder Woman's friend Dr. Helena Sandsmark. Using Amazon artifacts to simulate powers, Cassandra would join Wonder Woman's battles despite the latter's opposition. Amused, Zeus granted her powers "as a boon"... years later Cassandra discovered she was his daughter.
John Byrne also changes Donna Troy's origin to her being a Diana duplicate created by sorceress Magala using a magic mirror so that Diana had a playmate. In 2005, Phil Jimenez tries to fix the issue of Donna Troy's inconsistent origins by revealing that Donna remembers every life of her different incarnations prior to the death of the Multiverse, which implies every origin is true.
In 2011, DC publishes the Flashpoint event. The DC universe is rebooted once again, and the Wonder Woman family is completely revamped. In the new reality, Diana is daughter of Zeus, Donna is a woman made from magic clay to destroy Diana by Amazon rebels, Cassandra is a founding member of the Teen Titans and Diana's niece through her half-brother Lennox, and Lyta "Fury" Trevor is reimagined as Donna, daughter of Earth 2 Wonder Woman and Steppenwolf. Titans Hunt and DC Rebirth change more for Donna.
- 1941: Diana's first appearance.
- 1947: First flashback story featuring Diana as Wonder Girl.
- 1959: Robert Kanigher reintroduces Wonder Girl.
- 1960: Followed by a baby version, later named Wonder Tot.
- 1961: The start of the Impossible Stories: Wonder Woman and her younger selves, Wonder Tot and Wonder Girl, share adventures.
- 1965: A "Wonder Girl" first appears with the Teen Titans, though no mention is made of her origin other than that she is associated with Wonder Woman.
- 1969: Donna gets her first origin and a name, making her a normal human adopted by Amazons.
- 1983: Lyta Trevor, a.k.a. Fury, is introduced as a Wonder Girl for Earth-Two. She is the daughter of Diana and Steve Trevor.
- 1984: Who Is Donna Troy?", expands on the first origin.
- 1985–1986: Crisis On Infinite Earths happens.
- 1988: Who Is Wonder Girl?. Donna Troy's origin is changed, replacing Wonder Woman with Rhea.
- 1996: Cassandra Sandsmark is introduced.
- 1998: Donna Troy is given a new origin, this time as a duplicate from Diana created by a magic mirror.
- 2001: Titans: Who is Troia?. Dark Angel abducts Donna and claiming she is a cosmic anomaly, forces her to experience a cycle of countless tragic lives.
- 2002: Cassandra begins suspecting her biological father's real identity.
- 2006: Lyta Trevor's death.
- 2013: Fury's first appearance.
- 2015: Donna Troy's new clay origin.
- 2016: DC Rebirth relaunch. Wonder Woman's origin is reimagined again, ditching the majority of stories published after Flashpoint.
- 2017: Donna Troy states she's an orphan who doesn't remember her origins or her powers' before being adopted by the Amazons when she was seven. Later, Wonder Woman states the Amazons wiped out Donna's memories from being a clay doll created to kill Diana so Donna can lead a normal life.
- Wonder Woman Recommended Reading
- All-Star Comics (Volume 1)
- Comic Cavalcade (Volume 1)
- JLA (Volume 1)
- Sensation Comics (Volume 1)
- Sensation Comics Featuring Wonder Woman (Volume 1)
- Superman/Wonder Woman (Volume 1)
- The Legend of Wonder Woman (Volume 1)
- The Legend of Wonder Woman (Volume 2)
- Wonder Woman (Volume 1)
- Wonder Woman (Volume 2)
- Wonder Woman (Volume 3)
- Wonder Woman (Volume 4)
- Wonder Woman (Volume 5)
- Teen Titans Recommended Reading
- New Teen Titans (Volume 1)
- New Teen Titans (Volume 2)
- Tales of the New Teen Titans (Volume 1)
- Team Titans (Volume 1)
- Teen Titans (Volume 1)
- Teen Titans (Volume 2)
- Teen Titans (Volume 3)
- Teen Titans (Volume 4)
- Teen Titans (Volume 5)
- Teen Titans (Volume 6)
- Teen Titans Academy (Volume 1)
- Teen Titans Spotlight (Volume 1)
- Teen Titans Go! (Volume 1)
- Teen Titans: Year One (Volume 1)
- Titans (Volume 1)
- Titans (Volume 2)
- Wonder Woman Origins
- Wonder Woman Publication History
- Teen Titans Origins
- Teen Titans Publication History
- All-Star Comics #8
- Wonder Woman #23
- Wonder Woman #105
- Wonder Woman #113
- Wonder Woman #122
- Wonder Woman #124
- The Brave and the Bold #60
- Teen Titans #22
- Wonder Woman #300
- New Teen Titans #38
- Wonder Woman (Volume 2) #1
- Secret Origins (Volume 2) #12
- New Titans #50
- Wonder Woman (Volume 2) #105
- Wonder Woman (Volume 2) #134–Wonder Woman (Volume 2) #135
- Titans #25
- Wonder Woman (Volume 2) #181–Wonder Woman (Volume 2) #183
- Wonder Woman (Volume 2) #217
- DC Special: The Return of Donna Troy #1
- JSA #80
- Wonder Woman (Volume 4) #1
- Teen Titans (Volume 4) #1
- Teen Titans (Volume 4) #19
- Earth 2 #8
- Wonder Woman (Volume 4) #37
- Wonder Woman (Volume 5) #1
- Titans (Volume 3) #7
- Titans Annual (Volume 3) #1