Very few states in the United States can point to a diaspora of massive intra national migration.
Identified are six (6) massive waves of migration from Louisiana:
1812-1830
Orleans Parish to Haiti, Puerto Rico, Cuba and the Dominican Republic.
1850-1898
Natchitoches, Iberia, St Landry, Orleans, Plaquemines and St Bernard parishes to and from Veracruz and Tampico states of Mexico.
1910-1918
Migration from entire southern half of the state westward for increased economic opportunities, namely to California. Many soldiers returning from World War One settled in other regions of the country.
1927-1930
As a result of the Great Flood of 1927 (L’eau haute de 1927, Lô hôt de 1927), many families left homeless in South Louisiana fled westward for higher ground and economic opportunities. Texas was the initial stopping point. Many continued to Arizona, New Mexico and California.
1966-1975
At the collapse of segregation, when opportunities increased outside of the still bitterly segregated south, many Latin Louisianians fled to California (Los Ángeles, San Francisco, San Bernardino, Sacramento), Illinois (Chicago), Michigan (Détroit), Maryland/DC, Georgia (Atlanta), and Texas.
The American Gulf Coast Creoles encountered a very similar cultural history.
Similar to international diasporas, Louisianans fled en masse, and brought along with them their Latin culture, and continued to actively and purposely engage in its preservation and sustenance.
For instance, Okra was brought to Veracruz, Mexico by Louisiana Creoles, and is still grown there today, almost exclusively. Okra is an Afro-Creole vegetable, native to West Africa, but transported to Louisiana via the west African and Caribbean slave trade.
Populations of Hispanic Latins have not dwindled in the United States, primarily from Mexico and the Hispanic Caribbean, regions where Louisianans fled in the 19th century.
It is safe to argue that many of these Hispanic Latin American foreign nationals are bringing with them Louisiana Creole culture and ancestry, perhaps without knowing.
Of particular interest are the waves of migration of monolingual Louisiana French or Louisiana Creole, and/or bilingual Louisiana French/Louisiana Creole, inhabitants of Louisiana to other American states after the 1916 state mandate.