Nouns ending in -at are masculine.
The suffix often marks a status or condition.
Is soldat masculine or feminine?
lesoldat
The rule behind it
100% of -at nouns are masculine
In context
Le soldat dirigea son fusil vers l'homme.
The soldier aimed his gun at the man.
Bientôt, la cité fut occupée par les soldats.
The city was soon occupied by the soldiers.
Les soldats partagèrent leur nourriture avec les Indiens.
Soldiers shared their food with the Indians.