The Constitution of the United States requires that a census be conducted at least every 10 years for proper apportioning of taxes for Congressional Representatives. The 1790 census exceeded its Constitutional mandate to simply count the state's populations, setting the precedent of naming heads of households and categorizing persons by age and gender.
Each states' decennial schedules from 1790-1930 have been preserved on microfilm. ( LSU Libraries' Collection, housed in the basement of the Library in Government Publications, only extends to 1900 for Louisiana, and is unfortunately not complete). From 1790 to 1840, only heads of households were listed by name on the census forms. When using a census that names only the head of households, search for other records (such as marriage indexes), with that name to find other household members not listed in the census.
The census on microfilm LSU owns is limited. The only states in this collection include: Alabama, Arkansas, District of Columbia, Florida, Georgia, Kentucky, Louisiana, Maryland, Mississippi, Missouri, Pennsylvania, South Carolina, Tennessee, Texas, Virginia (and scattered census material for West Virginia). Information on other states may be located at the National Archives in Washington D.C., the regional branches of the National Archives, as well as the Bluebonnet Regional Branch of the East Baton Rouge Parish Library.
The collection of census material at LSU Libraries includes population schedules, agricultural census data, lists of manufactures, slave schedules, passenger lists for the port of New Orleans covering 1853-1899, social statistics, and scattered information concerning Defective, Dependent and Delinquent Classes. Other material that may be helpful for researching archives for genealogy information include Records of the Diocese of Louisiana and the "Floridas", New Orleans City Directories for years 1805-1945, New Orleans Christian Advocate concerning Marriage and Death Notices, Military Academy Letters, and Indian Affairs, just to name a few.