Burritos are very new. They were first made by someone wanting portable food to seek in the village during the Mexican Revolution around 1910-1920 in the Chihuahua area of northern Mexico where flour tortillas are very popular. A man made them and carried them to town in baskets on his burro, so we have food 'from a burro' not 'of a burro'. They then moved into California in the 1930s. I don't think that it came from egg rolls. Mexicans already had tortillas and they already had enchiladas which are sauced and rolled. It just makes sense that they would put something on and in a tortilla and eat it in hand.

My thanks to “galeanda” who's answer lead me to more research. I found two websites that support my conjecture that Chinese egg rolls are the father of Burritos with the mother Mexican or American. The combination of Sonoran meat and chilies etc. wrapped like an egg roll in a flour tortilla looks logical. The time frame for the conception of the Burrito coincides with the immigration of large numbers of Chinese to Northern Mexico very close to California and Arizona. My findings are below 1. The burrito, meaning literally little burro or donkey, became irreversibly linked to the tortilla- the modern burrito originated "in the dusty borderlands between Tucson and Los Angeles." The word burrito first saw print in America in 1934. It was sold at Los Angeles's famed El Cholo Spanish CafÚ during the 1930s. Sonoran cookery developed in Arizona. Carlotta Flores maintains that the Mexican cookery in Tucson was "a unique cuisine not found in any other border town. Although you may recognize the names of some dishes tacos, tamales, enchiladas, BURROS (my bold letters), chimichangas, chile colorado our way of preparing them is different from anywhere else in the world." This cookery is exemplified by the food served at Tucson's El Charro CafÚ, which opened in 1922 and in Mesa, Arizona, the El Charro Restaurant and Cocktail Lounge opened in 1919. http://food.oregonstate.edu/ref/culture/mexico_smith.html 3. Mexicali lays claim to the highest per capita concentration of Chinese residents in Mexico, by 1920 Mexicali's chinos outnumbered the mexicanos 10,000 to 700. The first Chinese to arrive in the area at the turn of the century signed on as laborers for the Colorado River Land Company, an American enterprise which designed and built an extensive irrigation system in the fertile Valle de Mexicali. Some immigrants came overland from America, while others sailed directly from China via the Pacific Ocean and the Sea of Cortez. http://www.mexconnect.com/mex_/travel/jcummings/jcchina.html

Well, sometimes, when a male burro and a female burro love each other very much, they play "find the canoli" and months later, a burrito is born.

"The burrito, meaning literally little burro or donkey, became irreversibly linked to the tortilla-rolled packages. Burrito lovers David Thomsen and Derek Wilson believe that the modern burrito originated "in the dusty borderlands between Tucson and Los Angeles." The word burrito first saw print in America in 1934. It was sold at Los Angeles' famed El Cholo Spanish Cafe during the 1930s. Burritos entered Mexican-American cuisine in other parts of the Southwest around the 1950s and went nationwide a decade later." http://tinyurl.com/yto2fu http://tinyurl.com/266rbh