Geography, geology & climate
They play a major role in world cuisines. Certain crops demand heavy rains, or sandy soil, or hot summers, or whatever. All this helps determine which raw materials will be available to the cook. Example: Southern Indians eat rice, northern Indians eat wheat.
Seasonal food shortages
Example: Lands with frigid winters need to preserve foods and incorporate them into their cold season diets.
Religion and custom
Certain foods or combinations of foods may be forbidden by religion or deplored by custom.
These world cuisine influencers include invasions. Initially, there is an aversion to the enemy's food. Eventually, assimilation occurs.
I've observed many times in my travels the obvious but telling difference in the agricultural results between a farmer using a animal pulled plow and a modern tractor.
This affects cooking styles. Take wood. It is ideal for grilling and slow, brick oven cooking. It is plentiful in forested lands like Eastern Europe but is scarce in countries like India and China.
Spread of New World foods
The European discovery of the New World had an explosive impact on the European diet. New foods were introduced in Europe including these now staples: potatoes, sweet potatoes, tomatoes, corn, chilies, allspice, chocolate, turkey and vanilla.
To illustrate, imagine:
Southern Italian cooking
Chinese Sichuan seasoning
without hot chilies
Irish and German diets
Introductions to the New World
The migration of foods did not move in only one direction. Chicken, beef, lamb, pork, wheat, and many fruits and vegetables (apples and oranges, for example) were brought to the Western hemisphere. The importation of the Old World horse also revolutionized New World agriculture.
The world cuisine exchange was beneficial. But today, national cuisines are being homogenized. This amalgamation is good if cooks can add the best dishes of other cultures to their repertoire. A Japanese adage says that tasting a new food adds 75 days to one's life. The trouble starts when new dishes displace the old, disrupting rather than enriching a traditional pattern of cooking and eating - and when the foods adopted represent the lowest common denominator rather than the best in the borrowed cuisine.
Some national and many regional ethnic cuisines are endangered culinary species. I believe those treasures are worth saving.