Showa period

The Shōwa period (昭和時代 Shōwa jidai?, literally "period of enlightened peace/harmony"), or Shōwa era, is the period of Japanese history corresponding to the reign of the Shōwa Emperor, Hirohito, from December 25, 1926 through January 7, 1989.

The Kamen Rider Series started in the Shōwa period, the Heisei period started during the early episodes of Kamen Rider Black RX. Episode 11 of RX was delayed by one week following Emperor Shōwa's death.

Being completely absent from television during the 1990s, the Kamen Rider franchise was kept alive mainly by stage shows, musical CDs, and the Shin, ZO, and J movies, though many fans classify the movies as part of the Showa series as they treat Shotaro Ishinomori's passing in 1998 the pinnacle of the Showa era. As of the film Heisei Rider vs. Showa Rider: Kamen Rider Taisen feat. Super Sentai, Toei has adopted and acknowledged this same classification for the 90s movies out of respect to Ishinomori and long time fans of the franchise.

The Heisei revival of the Kamen Rider Series began with Kamen Rider Kuuga in 2000, this was noted in Kamen Rider Decade (2009), the tenth Heisei era series which initally united the first nine Heisei series, also giving focus on the Shōwa period despite being only 38 years since the start of the series due to Decade's position as the 25th Rider hero.

Kamen Rider in the Showa era
Produced by Toru Hirayama (平山 亨 Hirayama Tōru?) and designed by Shotaro Ishinomori, creator of Cyborg 009, Kamen Rider premiered on April 3, 1971. Initially intended to be an adaptation of his Skull Man, Ishinomori and Hirayama redesigned the main character to resemble a grasshopper, supposedly chosen by his son. The hero Takeshi Hongo, portrayed by actor and stuntman Hiroshi Fujioka, was described as a transformed human (改造人間 kaizō ningen?), or cyborg. During the filming of episode 10, Fujioka was thrown off his motorcycle during the filming of a stunt and shattered both of his legs. His character would be phased out until the introduction of another transformed human in episode 14, Hayato Ichimonji as portrayed by Takeshi Sasaki, was introduced. The return of Fujioka and his character Hongo in episode 53 united the two actors and characters, as both Kamen Riders 1 and 2 would go on to appear in every show in the first half of the Shōwa Kamen Rider Series. The continuous run from April 1971 to January 1976 (Kamen Rider, V3, X, Amazon, Stronger) distinguished itself by featuring the recurrent mentor character, Tobei Tachibana.

After a four year hiatus following the finale of Kamen Rider Stronger, the series returned to television broadcast in October 1979 for two years with The New Kamen Rider (featuring Skyrider) and Kamen Rider Super-1. In these new shows, the role of Tachibana was replaced by a similar character named Genjiro Tani (谷 源次郎 Tani Genjirō?). The broadcast of yearly new shows ended briefly in the 1980s, punctuated by the airing of the Kamen Rider ZX special, Birth of the 10th! Kamen Riders All Together!! in 1984 which became the last project in the franchise to be produced by Hirayama.

In 1987, Kamen Rider Black premiered and was the first series that neither indicated nor hinted at any relationship with its predecessors. Black was also the first show in the franchise to feature a direct sequel, Kamen Rider Black RX, the basis of Saban's Americanized Masked Rider. RX's finale showed the ten previous Riders return to help Black RX defeat the Crisis Empire. Kamen Rider Black RX was the final show to be produced during the Shōwa era, with the franchise only resuming production by the end of the 20th century. The manga Kamen Rider Black acted as a novelization and reimagination of the Black/RX series' continuity.
 * continued in Kamen Rider in the Heisei period.

TV series

 * Kamen Rider (仮面ライダー Kamen Raidā?) (1971-73)
 * Kamen Rider V3 (仮面ライダーV3 Kamen Raidā Buisurī?) (1973-74)
 * Kamen Rider X (仮面ライダーX Kamen Raidā Ekkusu?) (1971-74)
 * Kamen Rider Amazon (仮面ライダーアマゾン Kamen Raidā Amazon?) (1974-75)
 * Kamen Rider Stronger (仮面ライダーストロンガー Kamen Raidā Sutorongā?) (1975-76)
 * Kamen Rider (Skyrider) (仮面ライダー（スカイライダー） Kamen Raidā (Sukairaidā?) (1979-80)
 * Kamen Rider Super-1 (仮面ライダースーパー１ Kamen Raidā Sūpā Wan?) (1980-81)
 * Birth of the 10th! Kamen Riders All Together!! (10号誕生！仮面ライダー全員集合!! Jūgō Tanjō! Kamen Raidā Zen'in Shūgō!!?) (1984)
 * Kamen Rider Black (仮面ライダーBLACK Kamen Raidā Burakku?) (1987-88)
 * Kamen Rider Black RX (仮面ライダーBLACK RX Kamen Raidā Burakku Aru Ekkusu?) (1988-89)

TV Specials

 * 1976: All Together! Seven Kamen Riders
 * 1979: Immortal Kamen Rider Special
 * 1984: Birth of the 10th! Kamen Riders All Together!!
 * 1987: This is Kamen Rider Black
 * 1988: Kamen Rider 1 to RX: Big Gathering

Theatrical releases

 * 1971: Go Go Kamen Rider
 * 1972: Kamen Rider vs. Shocker
 * 1972: Kamen Rider vs. Hell Ambassador
 * 1973: Kamen Rider V3
 * 1973: Kamen Rider V3 vs. the Destron Monsters
 * 1974: Kamen Rider X
 * 1974: Five Riders vs. King Dark
 * 1975: Kamen Rider Amazon
 * 1975: Kamen Rider Stronger
 * 1980: Eight Riders vs. Galaxy King
 * 1981: Kamen Rider Super-1
 * 1988: Kamen Rider Black: Hurry to Onigashima
 * 1988: Kamen Rider Black: Terrifying! The Phantom House of Devil Pass
 * 1989: Kamen Rider BLACK RX: Running Around the World - 3-D theme park special