attendants; retinue
Refers to a group of people accompanying an important person, often in a historical or formal context. The kanji spelling 供勢 is rare; the word is typically written in kana.
The shogun entered Edo with a large retinue.
The word is composed of 供 (attendant) and 勢 (force, group). The exact historical derivation is uncertain, but it likely originated as a term for a group of attendants or soldiers accompanying a lord.