Definition & Meaning of "an army marches on its stomach"

What is the origin of the proverb "an army marches on its stomach" and when to use it?

The origin of the proverb "an army marches on its stomach" is commonly attributed to Napoleon Bonaparte. It underscores the essential role of sustenance in supporting physical strength, endurance, and the ability to carry out tasks. The proverb serves as a reminder that success, whether in military or other contexts, depends not only on skill and strategy but also on the foundational need for resources, particularly food.