conjunction
Dated literary conjunction meaning 'therefore' or 'so'. Used in formal or old-fashioned writing; in modern Japanese, だから or それゆえ is more common.
されば、この問題は慎重に扱わねばならない。
Therefore, this issue must be handled with care.
conjunction
well, then ...
Dated conjunction used when changing the topic or moving a conversation forward. Similar to modern さて or では.
されば、次の議題に移りましょう。
Well then, let's move on to the next topic.
interjection
that's right; indeed; absolutely
Dated interjection expressing strong agreement. Equivalent to modern その通り or まったく.
「彼の言うことはもっともだ」「されば」
"What he says is reasonable." "Indeed."
conjunction
... on earth?
Archaic conjunction indicating surprise or rhetorical questioning. Rare even in classical texts; often part of set expressions.
されば、いかなる理由があろうか。
What on earth could be the reason?
Classical Japanese conjunction derived from 然り (sari, 'to be so') + ば (ba, conditional particle), literally 'if it be so'. The exact historical development is uncertain, but it became a fixed expression for 'therefore' and topic-shifting.