1. Past tense of 'intervir' - to come between; to take part in something; to interrupt
The police intervened in the dispute.
A polícia interveio na disputa.
2. To step in or get involved in a situation, especially to resolve a conflict
She intervened on behalf of her friend.
Ela interveio em favor de sua amiga.
3. To occur or happen during a period of time
Several events intervened before the decision was made.
Vários eventos intervieram antes da decisão ser tomada.