The First World War initially complicated his
life. He preferred to paint outdoors, an
activity that then required an official
permit from spy-conscious bureaucrats. Even
with this document, an artist sketching
outdoors risked falling under suspicion of
being an enemy agent. Money for art purchases
Munnings attempted to enlist in a Hampshire
regiment, even offering the army two horses
that he owned in the hope he would be accepted.
In 1917, he secured a position examining
remounts at Calcot Park, near Reading,
Berkshire. Horses, many of them arriving from
Canada, were checked for diseases and parasites,
treated, then sent off to artillery, cavalry,
or supply units.