Mosiah 11:18

And it came to pass that king Noah sent his armies against them, and they were driven back, or they drove them back for a time; therefore, they returned rejoicing in their spoil.

King Noah sent his armies to fight them. They pushed the Lamanites back for a while. So they came back happy with the things they had taken from the Lamanites.

So King Noah sent his armies out, and they drove the Lamanites back—at least for a while. They came home celebrating their victory and the plunder they’d taken.