A hundred years of family history stretches from roughly the mid-1920s back to the 1920s — across four generations, through at least one World War, and often across national borders. The records that document this period are plentiful and increasingly accessible online. This guide maps the journey era by era, showing you what records exist, where to find them, and what to do when a particular generation is hard to trace.
Before You Start: Establish Your Baseline
The most important thing you can do before opening any database is to write down everything you already know. Sit down with a blank page or a tree tool and fill in what you know about yourself, your parents, and your grandparents. Dates and places do not need to be exact — approximate birth years and the name of the country or state is enough to start. Once you have your baseline, you will know where your documented knowledge ends and where archival research needs to begin.
Years 0“30 (approx. 1996“present)
Within Living Memory
This generation is fully within living memory. Your primary sources are living relatives, family documents at home, and official vital records.
- Interview living relatives — parents, aunts, uncles, older cousins. Ask for names, birth years, birthplaces, and countries of origin.
- Search home documents — birth certificates, passports, marriage certificates, old letters, and address books.
- Request vital records — birth, marriage, and death certificates are available by request from the state or county vital records office.
- Social Security Death Index (SSDI) — free to search, covers most US deaths since 1935. Gives name, birth date, death date, and state of last residence.
Years 30“60 (approx. 1966“1996)
Early Childhood of Today's Grandparents
This era often marks the transition from personal memory to records. You may still have living people who remember this period, but official records become increasingly important.
- City directories — published annually in most American cities from the 1860s through the 1990s, city directories list residents by address and occupation. Invaluable for tracking a family as they move between census years.
- Obituaries — newspaper obituaries from this period are often digitised and searchable on Newspapers.com, GenealogyBank, and through local library newspaper archives. Obituaries frequently list surviving relatives by name, which can extend a family group significantly.
- World War II military records — the draft registration cards for WWII (1940“1947) are searchable on Ancestry and FamilySearch and cover virtually every American man between 18 and 64.
- 1940 and 1950 US census — both are now publicly released and fully searchable online.
Years 60“100 (approx. 1926“1966)
The Early-to-Mid 20th Century
This is the richest era for American genealogical records. Census records, immigration records, and military records combine to give an unusually complete picture of family life.
- 1900“1930 US census — the detailed census records from this period are the backbone of research for this generation. The 1930 census is the last one available before the 72-year privacy period ends (the 1940 and 1950 being the two most recently released).
- Passenger lists and immigration records — if your ancestors immigrated in the late 19th or early 20th century, their arrival records are almost certainly searchable on Ancestry or FamilySearch. The post-1906 lists record the specific village of last residence.
- World War I draft cards — over 24 million men registered for the WWI draft between 1917 and 1918. The cards record name, address, age, occupation, employer, nearest relative, and physical description. They are fully indexed and free to view on FamilySearch.
- Death certificates — state-level death certificates become increasingly detailed from the 1910s onwards. They often record parents' names and birthplaces, giving you a direct bridge to the next generation back.
- Naturalization records — post-1906 declarations of intention and petitions for naturalization are among the most detailed records in the American archive for immigrant families.
When the Trail Goes Cold
At some point in every research project, a generation becomes difficult to trace. Common reasons include name changes at immigration, record destruction (courthouse fires, wartime destruction), oral history errors, and the simple fact that not everyone left a paper trail. When you hit a wall:
- Try every spelling variant of the surname. Names were recorded phonetically, and a single letter change can mean the difference between finding and not finding a record.
- Research siblings. If you cannot find your direct ancestor, look for their siblings in the same records. Siblings were born in the same place, often appear in the same census households as adults, and can confirm family details when your direct line is obscure.
- Look for collateral records. Church registers, probate records, land deeds, and voter rolls all create documentary evidence outside the main genealogical record sources. A land deed might record a father and son transacting property together, establishing a parent-child relationship that no other record documents.
- DNA testing. Autosomal DNA tests (AncestryDNA, 23andMe, MyHeritage DNA) identify genetic relatives. A second or third cousin match who has already researched their line can sometimes extend your tree past the documentary brick wall.
Tip: Build your tree as you research, adding what you find as you go. A visual tree helps you spot gaps immediately and keeps the big picture in focus as you dive into individual record searches.
Map your family history visually
Build My Family is a free tree builder designed for exactly this kind of research. Add members, record what you find, and export to GEDCOM for cross-referencing on other platforms.
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