Also . . . What did people use for plastic before plastics were around?

Celluloid (1871) is recognized as the first modern plastic. It was
invented to replace ivory on piano keys and in billiard balls.
Celluloid is composed of cellulose nitrate and camphor. This flexible
plastic is what made the invention of motion pictures possible.

Bakelite (1909)[TM} was the first plastic to stay rigid when
reheated. The inventor was Leo Baekeland from Belgium. When you
dropped an old radio or appliance made of this stuff on the floor,
it would shatter.

Cellophane (1912) was invented as a clear sheet wrapper for food.

Phenolic (1924) was a thermosetting resin. When an old radio or
appliance burned out, this is what usually caused that pungent
odor. (Young people raised on solid state equipment are not aware
that old tube electronics with high voltage power frequently burned
out!)

My first introduction to modern injection molded plastic was in
American Flyer trains. Plastic of the late 40s was not robust and
could sag when it got too warm. If you used too strong a cleaning
solution it would melt! Some of the trains actually had a sag in
the top coming out of the mold.

During WWII, all my toys were made out of wood. The few plastics
around were not popular and metal was scarce because of scrap metal
drives for the war effort. (My mother had to wash out cans and
crush them flat for the war effort recycling.)

What about before plastics?

People used horns, bone, sea shells, mica, tusks, horses hooves,
plaster, wood, leather and tortoise shell for such items as combs, buttons, and implement handles, etc.

Hooves could be sliced off in sheets and then die punched out for
items like buttons.