Sengoku jidai

The was an unstable period of time in Japan from about the 15th century to the 17th century in which political, social and military unrest was common place. It was a time of war and chaos and constitutes the latter part of the "Feudal era" of Japan common known as "Feudal Japan". The Sengoku period was roughly 500 years before Kagome's time in the modern era: the Heisei era.

Explanation of time travel
The modern time is "-X-", a period in the Sengoku jidai is "-Y-", and 50 years before -Y- is "-Z-". At -Z-, Kikyō dies soon after sealing Inuyasha to the Goshinboku, causing him to go into suspended animation. She is then cremated with the jewel. 50 years pass and the story takes place at -Y-, where Inuyasha is still in suspended animation. At -X-, Kagome Higurashi, the 20th century reincarnation of Kikyō, is pulled into the Bone-Eater's Well bringing the jewel embedded in her body with her. She ends up at -Y- where she frees Inuyasha and they start their journey together.



Dates & Terminology

 * Although the series takes place in the Sengoku period, in the English dub this is often simply translated as the "Feudal era". While this is not wholly inaccurate factually, as feudalism did exist at the time, it is nevertheless an inaccurate translation of the term "sengoku jidai". The so-called "feudal era" of Japan is a much broader time period that stretches for many hundreds of years (c.1185-1871), and only encompasses the sengoku jidai (1467-1615) as one small part (roughly 20% of the overall feudal epoch). Kagome also sometimes refers to the feudal era as the "middle ages" in English, a term which actually refers to a much earlier European time period, and is not used to describe any era in Japan's history. The correct translation for sengoku jidai should be the "Warring States Period", as the corresponding kanji 戰國時代 stems from the Ancient Chinese period of the same name.
 * It is explicitly stated that the Band of Seven were executed 15 years before the start of the series by the northern warlords, and a samurai tells Jakotsu that a spectre over a decade old wouldn't recognize a matchlock rifle. As matchlock firearms first appeared in Japan in 1543, this suggests that the Band of Seven was defeated a decade or more prior to 1543 and that the series therefore takes place between 1543 and 1553.
 * Additionally, Kagome initially mistakes the young samurai Amari Nobunaga for a young . As Oda Nobunaga was born in 1534, he would have been a teenager during the 1547-1553 time period, justifying Kagome's misidentification. The weight of canonical evidence therefore overwhelmingly suggests that c.1543-1553 is the correct, approximate time frame for the events of the series. During the main events of the series, Oda Nobunaga was still referred to as the "Owari no ōutsuke" (lit. "Fool of Owari"), and had not yet become a conqueror; Amari Nobunaga even refers to him as a "big idiot" and demands Kagome not mistake the two of them.
 * Furthermore, the presence of the independent Takeda and Hōjō clans suggests a time period for the series that predates 1582 and 1591, as these are the dates the Takeda and Hōjō were defeated by Oda Nobunaga and Toyotomi Hideyoshi, respectively.
 * Therefore, although the series suggests that Kagome travels approximately 500 years into the past, this would likely place her in or around the vicinity of the late 15th century, either prior to or at the very start of the Sengoku era. Given that Kagome lives in the late 20th century (1997) and that the series can be dated to within 9 years after 1543 (see above), it would be more accurate to say that she travels back in time by a measurement of about 450 years.
 * Nevertheless, Myōga makes an inconsistent claim in InuYasha the Movie: Affections Touching Across Time that the occurred 200 years prior. If this were interpreted literally, this would put the time frame of the series between 1474 and 1481, which is impossible given the presence of the matchlock rifles used against the Band of Seven, mentioned above. This would mean that Myōga's estimate of the year of the Mongol invasions was off by 62 years at least, though it is possible that Myōga was merely rounding down to the nearest whole century (dates for past events in the series are usually given as round, easily recited numbers like 10, 50, or 200).