In the "Rising sun tokusatsu blog", Aoi Kurenai has posted a post about the seven eras of sentai, which goes into detail on the history of Super Sentai.
Here it is: http://risingsuntokusatsu.com/2012/09/19/the-seven-eras-of-sentai/
However, if I agree with him in a lot of his statements, I also have some points where I disagree with him. That's why I've decided to write my own post about the history of Super Sentai
1) First era: 1975-1977 : the Ishinomori era : Goranger-JAKQ
It's the first era, with the first Super Sentai series. At that time, there wasn't yet the giant robot and the monsters of the week growing bigger in sentai, and in fact, in a lot of ways, those series have a lot of similarities with other series written at the same time (the Kamen Rider series, Kikaider ...) : the series were very episodic, focused on a human-sized Kaijin, and the enemies were terrorist like groups, with mostly one Commander at a time, and a mysterious Big Bad which true nature isn't revealed until the end of the series. Goranger has even a similar villain concept as the first Kamen Rider series, with first, just the Big Bad, and the other villains are Kaijin of the week, and, later, one general at a time. JAKQ had even in common with a lot of Ishinomori toku the "Cyborg ("Kaizo-Ningen") hero concept. The main original point was that unlike most toku shows of that era, instead of one (or two) heroes, there was a real group of heroes, within a military organization. Goranger was very successful, and introduced the "colored hero group" concept. However JAKQ Dengekitai was much less successful, and, as a result, had some drastic changes, notably by introducing more comedy, a new Big Bad and the character of Big One, but that wasn't enough to save the series that was stopped after only 35 episodes.
At the time, the sentai franchise wasn't called "Super Sentai" and those two shows have even only be included in the Super Sentai franchise retrospectively, during the 90'. However, those series were very important, since they were the ones that introduced the basic concepts of a sentai series, and a lot of important writers (Shouzo Uehara, Susumu Takaku, and Hirihisa Soda as a secondary writer), were involved in those two shows, and would become very important writers in following sentai series.
2) Second era: the Uehara era : Battle Fever - Sun Vulcan (1979-1982)
Even if Uehara had already been the head writer of both Goranger and JAKQ, those three series belong to a separate era. Indeed, it's during that era that introduced some of the more important concepts that define the Super Sentai franchise: the giant robot fighting the giant monster.
Those concepts have been pretty much taken from the "Spiderman" toku show (which had the same writers, btw), who used them, in the climactic fights at the end of each episodes. In fact, in Battle Fever J, Marvel was involved much like it was in "Spiderman". Initially, those shows were the first real "Super Sentai" series. Like in the Goranger era, the series were very episodic, and the heroes were mostly investigating the bad stuff that the MOTW were doing in Japan. There weren't any long running plot. Interestingly, most of the field main villains were female (Salome, Keller and Mirror, the Zero Girls, Amazon Killer). However, some series introduced new concepts that would be used later (like Denziman having non professionnal sentai warriors, with a mascot-like mentor). Besides, Denziman used a transforming robot, and Sun Vulcan introduced the first "combining mechas" in Super Sentai.
3) Third era: the Soda era (Goggle V- Fiveman) 1982-1991
That era is named after Hirohisa Soda, who has been the head writer of 9 Super Sentai series which completely changed how the franchise would be made. That era can be divided in three parts:
- First part: GoggleV-Dynaman : that era is pretty much a transition era between the Uehara era and the majors Soda sentai series. GoggleV and Dynaman share with the Uehara series a pretty episodic concept. However, those series were pretty more light hearted and kid friendly (example, the "Computer Boys and Girls" in Goggle V) However those series have the classic "Soda villain" group, with a Big Bad, two or three human looking generals (with one female among them), and additional villains coming later. Besides, the rivalries between heroes and villains were more explored, and lastly, Dynaman introduced, with the Black Knight storyline, a true long running arc. At that time, Hirohisa Soda was slowly introducing his concepts, but kept the initial Super Sentai episodic format.
Second part : Bioman-Liveman : those series are the peak of creativity of Hirohisa Soda, who began to introduce majors concepts, like long running arcs, multidimensional villains, deep rivalries between heroes and villains. The tone was more serious than during the GoggleV-Dynaman era, and some important concepts appeared from the first time in Super sentai:
- female rangers that were not Pink rangers, with new colors (mostly Yellow, but also White and Blue), and teams with two girls
- villains that survived at the end of the series, and at the end became the heroes's allies (like Shima, Gator and Gyodai in Changeman, Igam in Maskman and Gou/ Oblar in Liveman)
- the villains's motivations were explored in more detail ; Changeman for example had generals that were blackmailed by the Big Bad to fight for him, becuas eotherwise their planets would be destroyed forever ; Liveman even introduced villains that were the heroes's former friends; and in Maskman, not all the Tube were evil villains.
- unlike previous sentai series that were mostly episodic, those series were very storyline driven.
Those series (except Maskman) had a very science fiction theme, (Bioman and Liveman put huge focus on science, Changeman and Flashman had a "space drama" feeling)
Third part- Turboranger-Fiveman: those series were those where Soda began to show "burnout" , since he began to repeat ideas that has been used in his previous series. The season quality was not as good as previous series. However, Soda still managed to introduce some new concepts : the "high school" sentai in Turboranger, and the "sibling" sentai in Fiveman, two concepts that would be used later. Moreover, Turboranger also introduced some fantasy in Super Sentai (while the Uehara series were mostly spy/ military series, and Soda series were sci-fi series) with the fairies. Turboranger and Fiveman also had a lighter tone than the previous Soda series, and were more kid friendly.
After Fiveman, Soda left the sentai franchise. The next series would be Jetman.
Jetman can be seen as a transition series, between the Soda era, and the next era, the "Sugimura era".
Jetman was penned by Inoue, who has been an important secondary writer of Hirohisa Soda during his last five sentai series as main writer. Jetman was a pretty "one of a kind" sentai, with a lot of "soap opera" like drama, with complicated love stories, a love triangle between three heroes, and even love conflicts within the villains group, and between the main heroes and some of the villains. Inoue would put his own personality in that show, and Jetman really uses tropes that Inoue liked a lot an would introduce in his later Kamen Rider series. Jetman was a huge success, but was a pretty much "one of a kind " sentai. However, Jetman used very different concepts than the ones used during the Soda era, and helped bring a new personality to Super Sentai, before the beginning of a new era. Besides, Jetman esthetics (the mechas, the monsters, the main villains) were more like the Sugimura era than the Soda era.
Fourth era: the Sugimura era : Zyuranger-Ohranger (1992-1996)
Named after the main writer of those four sentai series, Noboru Sugimura. That era introduced very important concepts in Super Sentai:
- the "fantasy theme" would be very important during that era, with Zyuranger, Dairanger and Kakuranger all using mythology themes; Zyuranger mostly used Western myths, Dairanger, Chinese mythology, and Kakuranger used Japanese mythology, wit the Yokai, and used the classic ninja theme.
- the importance of animal mechas: even if the first animal mechas were used in Liveman, the Sugimura era was the frist when animals began being the main mecha theme: Zyuranger used prehistoric animals, Dairanger, mythology animals, and Kakuranger used modern time animals.
- the introduction of the "additional ranger" concept, or rather the "sixth ranger concept"; even if JAKQ and Liveman already used additional ranger, it must be noted that neither of those teams started with five rangers; Zyuranger was the first one who used a long term sixth ranger.
- Series would become even more wacky, with very bizarre concepts: Dairanger had very weird villains esthetics, and the Kakuranger villains were completely crazy. Kakuranger had also a lot of comedy, with, at the beginning, a crazy narrator, slacker heroes and silly villains.
- the enemies grus were very different; each series used very different concepts
- Ohranger is an interesting case, since it has both very old school sentai concepts (the military theme, a dark tone, especially at the beginning; besides, old school writers were back for Ohranger, and at first, an episodic format) and Sugimura era concepts ( the mechas esthetics, some fantasy concepts, with King Ranger, and of course, the wackiness that appeared later). Ohranger was unique also because of its very diverse mechas concepts (ancient civilisations mechas, with some being animal like, but also geometric shape mechas (the Oh Blockers))
After Ohranger, it would be the end of that third era.
It's during that time that a new producer, Shigenori Takatera would leave his mark on the Super Sentai franchise
Fifth era: the Takadera era: Carranger- Timeranger (1996-2001)
Even if Takatera wasn't the producer of all those shows (GogoV and Timeranger were produced by Jun Hikasa), those shows can be grouped in a same era.
Carranger is a special case : it's a very unique series, because of its complete parodic tone, and can be seen as a transition series. Being penned by Yoshio Urasawa, who was a very important writer for the Toei comedy toku franchise "Toei Fushigi Comedy", Carranger was pretty much a one of a kind sentai series, with all the characters beign completely over the top, but using very funny comedy and having nice storytelling.
Carranger was the big return of vehicle themed mechas.
Megaranger, Gingaman, GogoV and Timeranger showed a pretty new tone compared to the previous series; it used new head writers (Junki Takegami, Yasuko Kobayashi); most of those series had a serious tone, with important focus on the main heroes. Those sentai series had a sci-fi feeling again (except Gingaman, who was more fantasy themed). They put also an important focus on storytelling, and despite its fantasy theme, Gingaman followed the trend of the others shows.
That era ended with Timeranger, because of its weak toy sales.
Gaoranger, the series that followed that era was pretty much a transition sentai series. It used a deliberately simple concepts, with the heroes being by themselves, isolated from the rest of the world to fight the villains. It used the demon villain concept used earlier in sentai series like Turboranger and GogoV. Moreover, Gao used more than ever the "animal mecha" concept, with important use of CGI for the mechas. Gao was a huge success, both rating wise and toy sales wise, and after Gao, followed the sixth era of sentai, that I'm gonna call the "Experimental era"
Sixth era: the "Experimental era": Hurricanger-Gekiranger (2002-2008)
Even if Super Sentai has been experimenting since its beginning, never it has so much tried different concepts than during that era.
- During that era, while most previous series used the classic "five man sentai (with, starting with Zyuranger, a sixth hero appearing at the middle of the series (Liveman, JAKQ and Sun Vulcan being isolated exceptions), that era used very different concepts of hero groups, with only three of those six series having the classic "five man team" at the beginning:
- Hurricanger used two rival sentai teams, a three member team (the main Hurricanger) and a two member team (the Gouraigers, who were siblings)); those two groups would later become allies with the introduction of a sixth hero later, who didn't have a human face (despite being human, and using plenty of different appearances (played by former sentai actors)
- Abaranger was a three man team, but with a fourth hero being there since the beginning, even if he would be unavailable as a sentai henshin ranger for different reasons through the show, and a sixth ranger that would be evil during most of the series.
- Dekaranger used the classic " five man team with a sixth appearing mid-series", but also had the mentor be a henshin hero (Doggie Kruger) even if he would only henshin in the most difficult cases only; Dekaranger would also have one shot henshin heroines.
-Magiranger used the classic "five +one " hero concept, but also had two additional heroes, including one appearing at the beginning of the series (Magimother) and another having a design similar to the one he had as a villain (Wolzard) ; besides that series was a sibling team, the sixth was a mentor figure, and the additional rangers were the heroes's parents
- Boukenger was more standard, but the "sword ranger " Zubaan has to be mentioned
- Gekiranger was again a three man team, but had two additional rangers appearing at the middle, (Violet, first, and then, once Violet's intro arc was over, Gekichopper). Moreover, the two main villains had a lot of focus and at the end, became also "Bangai hero": they even had mechas that could combine with the heroes's.
During that era, there were a lot of different head writers; but the most consistent presence as a writer was Naruhisa Arakawa, who was head writer of two series (Abaranger and Dekaranger) and secondary writer in all the others.
During that era, the series were either very plot driven with huge focus on storytelling and world building, with an important villain and supporting character cast, like in Hurricanger, Magiranger and Gekiranger: or very episodic, like Dekaranger and Boukenger, which had professional sentai teams (cops for the former, treasure hunters for the latter); it must be noticed that in Dekaranger and Boukenger, the finale isn't the conclusion of the series, but rather just the end of one story among others, since both cop work and treasure hunting won't stop after the finale.
Abaranger was pretty at the middle, a little less plot driven than Hurri, Magi and Geki, and more focus on the characters, but despite that, not episodic, unlike Deka and Bouken.
Gekiranger's low sales brought the end of that era
Seventh era: the modern era: Go-onger -Go-Busters (2008-2013)
That era is pretty remarkable because during that era, the series focused much less than before on storytelling. As a result, the series relied much more than before on their gimmicks, notably the mechas, with unfortunately very bulky "clusterf*ck" mechas, and the use tof the year's concepts (like the Engines in Go-onger, the Samurai theme in Shinkenger, the "sentai tributes and ranger keys" in Gokaiger for example).
Those series suffered a lot either of plot stalling, with the villains doing little during a big bunch of the series (like the Gedoushuu in Shinkenger , the Zangyack in Gokaiger or the Vaglass in Go-Busters) or of pretty uninteresting villain groups (like the Warstar and Yuumajuu of Goseiger, or the Gaiark of Go-onger).
The quality of those series wasn't as high as the previous one, the best ones (Shinkenger, Gokaiger) being so because of their well fleshed heroes.
Now that Kyoryuger has started, the big question is : is Kyoryuger is gonna belong to that "modern era", or is it gonna be the start of a new era?
We'll have to wait to have the answer.