How to trace American immigrant ancestors

Passenger lists are often the first stop when tracing immigrants to the US. These documents can reveal names, ages, occupations, places of origin, and sometimes even next of kin for people who travelled from Britain and Ireland to North America. You can search passenger lists online on Findmypast and other genealogy websites. 

When searching, be prepared for name variations. Surnames were often misspelt or changed entirely, especially for Irish and Eastern European immigrants, so ensure you try alternate spellings, nicknames, and phonetic variations if you can't find the person you're looking for. 

From Ellis to Angel Island: common ports of passenger arrival 

In the 18th and 19th centuries, popular ports of entry for immigrants into the United States included:  

• New York (Ellis Island & Castle Garden)  
• Boston  
• Philadelphia  
• Baltimore  
• San Francisco (especially for Asian immigrants)  

Castle Garden operated from 1820–1892, followed by Ellis Island (1892–1954), records of which are both of which are searchable on Findmypast. If your ancestors left the UK, be sure to check Passenger Lists Leaving the UK 1890–1960, which is a vital collection to track departures in this period.  

Some immigrants travelled indirectly to the United States, via Canada, South America, or other routes, due to changing immigration laws. These journeys will undoubtedly be trickier to trace and will require you to explore different record collections to build a full picture. 

Many immigrants pursued citizenship, and US naturalisation documents are packed with detail - birthplaces, immigration dates, occupations and more.  

The naturalisation process usually involved filing a Declaration of Intent and later a Petition for Naturalisation, often several years apart. Documents relating to both steps have been preserved and made searchable online.  

Thanks to standardisation, records from after 1906 are particularly useful. You can search the indexes of these online via Findmypast, which is a simple starting point before you delve deeper to view the full documents in US archives. 

The US census, taken every 10 years since 1790, is one of the most valuable tools for tracing ancestors after they arrived in the United States. US Census records are searchable on Findmypast. 

The 1900 and 1910 US censuses are especially helpful, as they list immigration years and naturalisation status. Later censuses also include occupation, literacy, and home ownership, helping you understand how your ancestors’ lives unfolded in the New World.  

Was your ancestor fleeing famine in Ireland, escaping political upheaval, or seeking work in America’s growing cities? Knowing why they left can help you understand when, and what routes or records are most relevant.  

Scots-Irish ancestors, for example, often migrated in waves during the 1700s, while Irish famine migration peaked in the late 1840s. Economic hardship, industrialisation, and wars all played a role in shaping migration patterns.  

Historical newspapers offer a glimpse into their world and what drove them to move overseas. You can explore digitised old newspapers via the Findmypast newspaper collection, searching by name or keyword and narrowing down your results by location, date or title. Once you've found the pages that build up a detailed picture of their immigration journey, clip the headlines that matter and save your findings in a Collection.  

Though best known for UK and Irish records, Findmypast also holds rich US resources which are especially useful for British and Irish descendants. To trace American ancestors on their journeys around the globe, consider searching these vital records:  

• US birth, marriage, and death records  
• New York Passenger Lists & Arrivals  
• Military records from WW1, WW2 and beyond  
• School, work and trade records  
• Directories and Scotch-Irish social histories  
• Catholic Heritage Archive, with sacramental registers from major US cities 
• Global collections for immigrants who travelled on to Canada, Australia or the Caribbean  

Tracing your immigrant ancestry means rediscovering stories of hardship, heartbreak, adventure and triumph. Follow their journey across the ocean, whether into bustling cities or remote frontiers, and weave their story into the fabric of your family tree.