All 3 Uses of

intervene

in

A Room With A View

At the moment when she was about to judge him her cousin's voice had intervened, and, ever since, it was Miss Bartlett who had dominated; Miss Bartlett who, even now, could be heard sighing into a crack in the partition wall; Miss Bartlett, who had really been neither pliable nor humble nor inconsistent.†
Chpt 7

intervened = got involved or came between

They have sinned against Eros and against Pallas Athene, and not by any heavenly intervention, but by the ordinary course of nature, those allied deities will be avenged.†
Chpt 17 *

intervention = get involved; or come between

Definitions:

(1) (intervene as in: intervened in the war)
the process of getting involved to influence an outcome
The exact meaning of intervention can depend upon its context. For example:
- "intervention program for at-risk youth" -- a process of trying to influence the direction of someone's life
- "medical intervention" -- action taken to improve a medical outcome
- "military intervention" -- interference by a government in affairs of another government (in this case to interfere militarily)
- "had a family intervention" -- an organized meeting of family members to encourage someone (who is often surprised) to recognize and work at solving a problem such as substance abuse
(2) (intervene as in: in the intervening years)
something between two other things -- especially the passage of time between two events
(3) (meaning too rare to warrant focus)
Much more rarely, intervene can mean:
in various senses, including:
- to verbally interrupt -- as in "Not now!' she intervened."
- to be physically between -- as in: "You can't walk from one hill to the other because an impassable river intervenes."