By Alvin Alexander. Last updated: June 4, 2016
To create an order by query using the find method of the MongoDB Casbah driver (Scala), use the sort method, as shown in this example:
def findAll(): List[Url] = {
// 1 == ascending, -1 == descending
var urlsAsDbObjects = MongoFactory.urlsCollection.find().sort(MongoDBObject("created" -> -1))
(for (u <- urlsAsDbObjects) yield convertDbObjectToUrl(u)).toList
}
As shown in the comment, specify 1 to order by the given field in ascending order, and specify -1 to order by the field in descending order.
I found some of this information at this Google Groups URL.

