Hispanics who want to trace their heritage back to Mexico could do so as historical resources are published online for the first time.
America's largest minority group will be able to look for their descendents as the full 1930 Mexican census is to be made open for public access, reports the Associated Press.
Previously records were only kept by the church, which began recording information in 1950, so this earlier census material could open doors to many Mexicans and Mexican-Americans who are interested to find out where they come from.
Programmes like Who Do You Think You Are have encouraged people to become more intrigued about their heritage.
The information will be made available on Ancestry.com in English and Spanish.
Eduardo Obregon Pagan, a history professor at Arizona State University who traced his roots to Puerto Rico and Mexico said: "Knowing where we came from and the forces that brought us to where we are today – it goes beyond our immediate story."
The 1930 Mexican Census covers categories such as marriage, home ownership, occupation and even serious illnesses.
As of 2009, Mexican-Americans made up 10.3 per cent of the US population.