"There were 4623 people within the county boundaries in 1860 and that was out of 31 million in the whole nation," Sharon Hiigel of Fresno Historical Society said.
There were no questionnaires mailed out to homes 150 years ago. Census takers had to visit every home in the county and record on this large ledger sheets basic information about every person who lived there.
"It was a huge bound volume and they recorded information right across the page."
These original documents are now kept in vaults at the Kearney Mansion Museum, preserved by the Fresno Historical Society.
"Every state was represented here and countries around the world, its fascinating to read."
Sharon Hiigel curator for the historical society says these records reflect what was happening in California in the mid 1800's, during the Gold Rush.
"There is a lady who came as a confectioner from Chile."
"The 1860 census reflects our history but it's a history that has continued; it's still enriching us, all the people coming."
The census questions haven't changed too much through the years.
"This year we've gone back to one of the simplest forms we've used in decades," Richard Flores, Census Partner Specialist said.
This year there will be no long forms just 10 questions that will provide generations to come a picture of what every city, county and state in the country looked like in 2010.
"It's still just as important now as it was back then," Richard Flores said.
The whole purpose of the census, to count the people for a fair and accurate representation in congress.
Census questionnaires will be mailed out march 15th and should be in your mailbox by the 17th.