In World War II, the "scorched earth" policy in retreat was first applied by the .....?

Now they are scorching Ukraine.

Newt, not just Napoleonic. It has been a common strategy from ancient times. Deprive your invading enemy of food, resources. Pretty obvious. The local peasants suffer more though.

Actually a recycled tactic from when Napoleon tried the same thing.

Newt, the question states ww2. in this case, Finland was the first. In 1939-40 in the winter war V Russia.

“…denying or destroying…”