The typical WWI airplane had no trim on any surface.
Pilot brute force kept the pointy end at the front.
With the Eindecker, this required a lot of muscle ALL the time, with both the vertical and horizontal full-flying, and the drag of the motor support shaft in its bearing forcing a continuous right turn which had to held off by the pilot.
Very late in the war the advantages of trim were being looked at.. The SE-5 had a trimming horizontal.
Fokker went from that awful comma-shaped all-flying rudder to a fixed vertical and a movable rudder, thereby immensely reducing the physical demands on the pilot.
The inverted horizontal, which is still in use today, acts to reduce the trim demands. Its nose up force increases directly with the nose-down moment of the wing as speed changes.
The Lockheed L-1011 has a full-flying horizontal, with an inverted airfoil. The C-130 horizontal is inverted, with a conventional fixed horizontal and moveable elevator.