no conocía a nadie

didn't know anyone

→ no
phrase Rare #31,617
didn't know anyone Uses the imperfect tense to describe not knowing anyone at a past time or over a period in the past. The personal a is required before nadie when it is the direct object of conocer.
SP: Cuando llegué a la universidad, no conocía a nadie.
EN: When I arrived at university, I didn't know anyone.

Tom dijo que no conocía a nadie que pudiera pilotar un helicóptero.

Tom said he didn't know anyone who could pilot a helicopter.

Parker no conocía a nadie hasta que Jones le tiró un platillo.

Parker didn't know anyone until Jones threw a saucer at him.

— Whiplash (2014)

Tom no conocía a nadie en la sala.

Tom didn't know anyone in the room.

Cuando llegué aquí no conocía a nadie.

When I got here, I didn't know anyone.

Le dije a Tom que no conocía a nadie que se llamara María.

I told Tom that I didn't know anyone named María.

Tom me dijo que no conocía a nadie llamado María.

Tom told me he didn't know anyone named María.

No conocía a nadie en la fiesta.

I didn’t know anyone at the party.

Tom no conocía a nadie.

Tom didn't know anyone.

Sin contar a Tom, no conocía a nadie ahí.

Apart from Tom, I didn’t know anyone there.