When the civil registration was introduced in 1811 or slightly earlier, the government required that all churches turn in their baptismal, marriage and burial records. These church records would become the foundation of the civil registration, where government officials could determine when a person was born, married and died.
If you are looking for a birth, marriage or death for the period prior to the civil registration, church records are the first place to go. They are still kept by the government and can be found in the archive in the capital of the province. Increasingly, they are becoming available online, either on the website of the archives or at Familysearch. You can use Genver to see whether the church records of the town where your ancestors came from are available at Familysearch.