If the early Islamic-era armies (from nearly a millenia later date granted) can be used as a yardstick, in pitched battles those apparently chiefly fought as close-order infantry backed by lots of infantry archery ("composite" troops capable of both archery and heavy-infantry melee combat were apparently common). The cavalry mostly acted as a scouting, flanking and pursuit force - largely because there simply wasn't much of it to go around, which rather limited what could be done with it. Or that's what I've read about them says anyway.

Granted, that's a big time leap but it would have been more or less the exact same people with the exact same resources (although mail changed to iron at some point) dealing with the exact same geography and sundry circumstances, without having been severely disturbed by any major foreign incursion I'm aware of, so...