Library and Archives Canada has just added a new searchable database for immigration to Canada before 1865. This is an important set of records since ships passenger lists to Canada before that year did not have to be archived.
In 1803, the British Parliament enacted legislation to regulate vessels carrying emigrants to North America. The master of the vessel was required to prepare a list of passengers. Unfortunately, few such lists have survived. So we must look to other sources for the names of our ancestors arriving in Canada before 1865.
Some lists have been identified and indexed by name in the LAC database. It also includes other types of records such as declarations of aliens and names of some Irish orphans. Search Immigrants to Canada Before 1865 at LAC
Other lists of immigrants to Canada before 1865 can be found at Ships to Canada