Scrutinizing the history of Japan with Western historiographical criteria invariably leads to misunderstandings, while the history of this country should be considered and perceived as Japanese historians do. Therefore, the division of eras, or rather those periods of history which conventionally bring order to events, as far as Japan is concerned are called eras as they give the name to the entire period of time to which they refer (for this reason sometimes these eras are also called periods). Many times the various eras take their name from epochal events or simply from the emperor, a figure perennially present in Japanese history even if often as a secondary figure. Roughly we can consider a prehistoric period, a protohistoric one (i.e. that period of Japanese history reported in other cultures, mainly in the Chinese one, as in the text Book of Han of the 1st century), and the properly historical period which is divided, as mentioned, in eras.
Writing, and therefore the possibility of narrating history, arrived in Japan with Buddhism (in its Mahāyāna acceptation, the Great Vehicle) around the middle of the 6th century: in fact, King Seong of the state of Baekje (Korea) made a gift to the monarch of Yamato (ancient name of Japan), the Emperor Kinmei, of a statue depicting the bodhisattva Kannon together with the scroll of a sutra written in Chinese. The text Nihon Shoki (The Chronicles of Japan, written in 720) reports the date of 538 or 552 depending on the calculations but in any case not very reliable.

Ancient Japan

Era	Period	To know more
Jōmon Era (縄文時代, Jōmon jidai)	c. 13.000 a.C. - c. 300 a.C.	Jōmon period (from Wikipedia)
Yayoi Era (弥生時代, Yayoi jidai)	c. 300 a.C. - c. 250	Yayoi period (from Wikipedia)
Kofun Era (古墳時代, Kofun jidai) or Era of the Ancient Tombs	c. 250 - c. 538	Kofun period (from Wikipedia)
Asuka Era (飛鳥時代, Asuka jidai)	c. 538 - c. 710	Asuka period (from Wikipedia)
Nara Era (奈良時代, Nara jidai)	c. 710 - c. 794	Nara period (from Wikipedia)
Heian Era (平安時代, Heian jidai)	c. 794 - c. 1185	Heian period (from Wikipedia)

The period in Japanese history from 250 to 710 is also called the Yamato period (大和時代, Yamato jidai). The name derives from the fact that during this historical era, the Japanese imperial court was established in the province of Yamato (corresponding to today's Nara prefecture, on the island of Honshū), and the term Yamato has since become synonymous with the whole of Japan.

"Feudal" Japan

Era	Period	To know more
Kamakura Era (鎌倉時代, Kamakura jidai)	c. 1185 - c. 1333	Kamakura period (from Wikipedia)
Muromachi Era (室町時代, Muromachi jidai)	c. 1336 - c. 1573	Muromachi period (from Wikipedia)
Azuchi–Momoyama Era (安土桃山時代, Azuchi–Momoyama jidai)	1568 - 1600	Azuchi–Momoyama period (from Wikipedia)

Straddling the Muromachi and Azuchi–Momoyama periods, bordering on the subsequent Edo period, lies an era of struggles and civil wars which is called the Warring States period, or also the Sengoku period (戦国時代, Sengoku jidai) (1454/1467 /1493 - 1568/1638). To know more: Sengoku period (from Wikipedia).

Premodern Japan

Era	Period	To know more
Edo Era (江戸時代, Edo jidai)	c. 1603 - c. 1868	Edo period (from Wikipedia)

Modern Japan

Era	Period	To know more
Meiji Era (明治時代, Meiji jidai)	1868 - 1912	Meiji period (from Wikipedia)
Taishō Era (大正時代, Taishō jidai)	1912 - 1926	Taishō period (from Wikipedia)
Shōwa Era (昭和時代, Shōwa jidai)	1926 - 1989	Shōwa period (from Wikipedia)
Heisei Era (平成)	1989 - 2019	Heisei period (from Wikipedia)
Reiwa Era (令和)	2019 -	Reiwa period (from Wikipedia)

Map of the Ancient Provinces of Japan (令制国, Ryōseikoku). The Ryōseikoku were the first-level administrative divisions of Japan from 600 to 1868. Solid province boundaries span from the Kamakura period (1185) to the Meiji Restoration (1868). In 712 Mutsu Province, containing all of Tōhoku, was divided into Dewa Province and Mutsu Province. The dotted boundaries are as follows: 11 provinces of Hokkaido were established in 1869 and dissolved into Hokkaido in 1882. In 1869, Mutsu Province was divided into 5 provinces, and Dewa Province was divided into 2 provinces until 1876. In 1869, Chishima Province with 5 districts was created, and in 1875 it included all of the Kuril Islands. The Satsunan Islands (薩南諸島, Satsunan-shotō) to the southwest were annexed to the Satsuma Domain in 1609.

Image attribution and explanatory text of the map: By Artanisen - Own work, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=120158080