ＡＩ時代の読書 非効率な出会いの意味 · 2026年11月3日
読書週間の源流は関東大震災後に始まった読書運動とされる。
The origin of Book Week is said to be a reading movement that began after the Great Kanto Earthquake.
とされる follows the noun phrase 読書運動 directly and presents the origin of Book Week as the generally accepted view, not as something the writer is personally claiming. Newspapers use it for received facts, official positions and established history, because it is more impersonal and authoritative than と言われている. Grammatically it is the passive of 〜とする ("to regard as"), so 〜とされる literally means "is regarded as"; it should not be confused with ordinary する-passives like 実施される.