Mecha Timeline
A work in progress!
Retro Robot Era
This era lacks many of the trademarks associated with the modern mecha genre, but has too much continuity with foundational Super Robot works for me to ignore it here.
1958
Tetsujin-28-go, by Mitsuteru Yokoyama, begins. This manga features a young boy and a giant robot controlled via remote. Yokoyama also created Sally the Witch, an early influential magical girl work.
1960
Tetsujin-28-go, the tokusatsu adaptation of the manga, airs.
1963
Tetsujin-28-go, the anime this time, airs.
1967
Giant Robo, another manga by Mitsuteru Yokoyama, begins. Recalling several motifs from Tetsujin-28-go, this work features a young boy and a semiautonomous giant robot controlled via radio wristwatch. The same year, it receives a tokusatsu adaptation through Toei.
1972
The Moon, by George Akiyama, begins publication. This manga features several children who gain the ability to psychically direct an ambiguously sentient mecha called "The Moon," built to seek justice in response to the Nietzschean "death of God." Decades later, this forms the basis for the manga Bokurano.
Super Robot Era
In this era the mecha genre more closely resembles its modern form. Iconic franchises like Mazinger and Getter Robo are established, and the Robot Romance trilogy is a proving ground for both a new depth of characterization and the rising generation of mecha creators. Thematic overlap with tokusatsu superhero shows is significant, culminating in the Super Sentai franchise adopting mecha as a recurring franchise element. Compare the specialized vehicle teams of Getter and co. to Thunderbirds.
Prominent Super Robot creator Go Nagai also created Cutie Honey, an early influential magical girl work.
1972
Mazinger Z, by Go Nagai, begins publication. This manga is the first to premise itself on a mecha piloted internally, and can be considered the origin of the Super Robot subgenre. Nagai was inspired by Astro Boy, Tetsujin-28, and wishing his car could grow legs while stuck in a traffic jam. An anime adaptation through Toei Animation and an additional manga adaptation of that anime are released before the end of the year.
Astroganger premieres almost simultaneously with Mazinger Z's first appearance. Like its Retro Robot predecessors, this anime features a young boy and a giant robot, but this robot is fully alive and autonomous. The human protagonist and the robot protagonist regularly merge in a transformation sequence to unlock their true potential.
Iron King is an example of a transformaton-based tokusatsu featuring a giant robot or cyborg, the titular Iron King. At this point there's already a history of giant transforming heroes like Ultraman, somewhat resembling giant robots but forming a distinct tradition. Further examples will be included when they represent some specifc exchange between the genres. For another intriguing edge case, see Dinosaur War Izenborg.
1973
Super Robot Red Baron was planned to bring mecha back to tokusatsu after a long absence as a 20th anniversary celebration for Nippon Television. Influence from both Giant Robo and Mazinger Z is notable, although the original proposal predates Mazinger Z. Two manga adaptations run alongside it, canceled early due to financial trouble with the sponsor.
Godzilla vs. Megalon features Jet Jaguar, another Ultraman-esque giant transforming hero, with some design elements reminiscent of Mazinger. Jet Jaguar is explicitly a robot, rather than a cyborg, but gains self-awareness and autonomy over the course of the film, protecting humanity against invading aliens.
1974
Denjin Zaborger is an unusual case, "street level" tokusatsu featuring a human-scale robot that transforms into a motorcycle. Demonstrates influence of mecha on tokusatsu, even if Zaborger itself isn't giant or piloted in humanoid form.
Super Robot Mach Baron returns the "Baron Series" to broadcast. Like the first it was canceled early. Also the first mecha series to get "combination robot" plastic models from Aoshima Bunka Kyozaisha.
Getter Robo, a collaboration between Go Nagai and Ken Ishikawa, launches an anime and manga near-simultaneously. This series introduced combining robots to the genre. Toei Animation and Nagai's studio, Dynamic Pro, are on their way to becoming dominant forces in the rising super robot genre.
Great Mazinger immediately follows the conclusion of Mazinger Z, sharing the same slot in the broadcast schedule. The sequel series was planned from relatively early in Mazinger Z's run, but the show's popularity delayed it repeatedly. Manga adaptations appear shortly after. Some kind of milestone crossed as the first mecha franchise to get multiple anime.
Chogokin toy line from Popy, most of the lineup is mechs
1975
Getter Robo G same slot
Brave Raideen you're up
Great Mazinger vs. Getter Robo, a short crossover between Nagai mecha, is shown in theaters. Later that year, Great Mazinger vs. Getter Robo G: Kuchu Daigekitotsu and Uchu Enban Daisenso release as a double feature
Steel Jeeg is Nagai+Toei again, but there's a toy deal with Takara to pay attention to. very popular in Italy???
UFO Robot Grendizer: in space! Nagai is more distant from this one's anime side of things.
1976
Groizer X it's Nagai again! Apparently!
UFO Warrior Daiapolon airs, gets a revised rebroadcast on a different network shortly after it ends.
Dino Mech Gaiking gets the Getter slot, Nagai created the concept but was denied credit. Nagai stops working with Toei after this. very early dino mech fusion, although i think Mazinger had a bit of that too. Supposedly cancelled early to make way for Jetter Mars.
Blocker Gundan 4 Machine Blaster now you're just messing with me
Magne Robo GaiKeen takes the Jeeg slot, Nagai no longer involved
Gowapper??? apparently also related to the magnet robots??
Combattler V kicks off Robot Romance, shared staff with Raideen
1977
Daitetsujin 17 aw yeah Ishinomori is on this one
Little Superman Ganbaron is the third entry in the Baron Series, differing in some important ways from its predecessors: The protagonists are now young children, and the series follows a "transforming hero" model for its first several episodes. Episode 14 introduces a combining robot, Daibaron. This is the first I'm aware of a toku series including both transforming heroes and giant mecha. Once more the series ends early due to financial trouble with the sponsor, with a "see you next week" left hanging.
Ginguiser there's so many of these
Mechander Robo takes Groizer or Daiapolon's slot, depending what channel you watched it on, another combiner. Same toy sponsor as Ganbaron. Ends the slot.
Voltes V vvvvvvv
Planetary Robot Danguard Ace takes the Mazinger timeslot, i actually have to look into this one. No more mecha in the slot but it's followed by another Matsumoto sci-fi anime.
Barattack takes GaiKeen's slot and ends the magnet robot series. And the mecha slot.
Zambot 3, directed by Yoshiyuki Tomino, the first of several Sunrise series sponsored by the Clover toy company
1978
Tosho Daimos ends the trilogy
Daitarn 3 Clover-Sunrise series continues in the same slot, also directed by Tomino, Gundam is up next
Daikengo may have followed up a Reideen rebroadcast? And then immediately followed by a Combattler rebroadcast
Spider-Man by Toei bridges the gap between street-level toku and mecha
1979
Battle Fever J takes the Robot Romance timeslot
Future Robot Daltanius shares a lot of the same staff with the Robot Romance trilogy, and is sometimes considered a fourth member of the set. Takes Spider-Man's slot.
Machine Saurer by Nagai