Documenting Unknown Dates

Genealogists and family historians often find themselves with unknown dates for events they have researched. How to capture this in a genealogical database is not immediately apparent to many of us. We think, “Perhaps I should enter ‘Unknown,’ or a question mark, or omit the date entirely.” After all that work, it seems like something should be documented to indicate that research has been done and no conclusion reached. Trying to force the date field to do more than it’s intended or capable of doing isn’t the solution. It could be an indication that we’re not confident that our research is well documented or that our plan is recorded. What should one enter in a genealogical database when the date of an event is unknown? How should one deal with that feeling of unease that’s causing them to look at the date field as a cure-all? This article will answer both questions for you. Let’s start with what to do with the unknown date.

Omit the Date

The best solution is not to enter anything at all in the date field for an event when the date is completely unknown. Naturally, if parts of the date are known, enter the partial date. This answer is more a matter of style than a rule, but it will serve you well for the reasons below.

Omitting Works with All Software

Omitting the date is the only approach universally supported by all genealogy software. Some genealogy software will allow you to enter something that’s obviously not a date, such as a question mark or the word “unknown.” MacFamilyTree will display a warning icon if the date can’t be parsed. Reunion 9 for Mac will present you with a warning dialog box explaining the problem and giving you the choice of going back to “fix” the problem or accept it as a custom date. Other software will steadfastly refuse to accept any entry it cannot understand as a date. iFamily for Leopard is an example of this approach.

There’s a good reason behind the applications preferring or requiring actual dates; any reasonably sophisticated genealogy software checks dates as they are entered. Typically the format of the date is checked to ensure that it is valid when entered. For instance, the program would refuse to accept 32 Jan 2009 as a date because there are never 32 days in the month of January. Most software also performs date feasibility (or coherence) checks. These checks are for conditions that ought to be impossible or extremely improbable and issue a warning or prevent the entry. An example of such a condition is a death date that precedes a birth date. These types of checks are meaningless for entries like a question mark or “unknown.”

Omitting an unknown date prevents validation and feasibility checks as well as date calculations, like the person’s age at an event, from being confounded. Unfortunately, it doesn’t prevent us from forgetting what research has been done. So how does one keep track of what’s been researched?

Log Your Research Efforts

The date field for an event isn’t the best place to indicate what you’ve investigated already. It’s better to keep a research log containing the subject being investigated, the research performed, and the results of the search. This approach ensures that you or other genealogist can know, potentially years later, what research was performed, how, and what evidence resulted. It makes it easy to have a colleague check your work to uncover missed opportunities. Finally, it makes preparing your proof statement easier as all the information is preserved and contained. This is important to do whether you find conclusive evidence or not.

Even with your painstaking research efforts safely preserved for future consideration, you may be wondering, “Wouldn’t the date field still be a good place to indicate that more research is needed?” It could be, but for the reasons above, it isn’t the best way. Besides, future research to-do items have a better place to reside.

Identify Next Research To-Dos in a Task List

Research tasks are best kept in a task list. Using the date field, or other event attributes for that matter, cannot compare to the benefits of using a dedicated to-do list. The list could be within your genealogy software, if that’s a built-in feature, or a stand-alone task manager. A modern task list application will enable you to filter and sort tasks in ways that will make your work more efficient and ensure you don’t forget what remains to be researched.

Feel Confident and Leave the Date Field Empty

Keeping a research task list and logging your research efforts will give you the confidence you need to leave fields unpopulated for unknown dates. You’ll solve more genealogical puzzles and leave even more helpful family history documentation for future generations. It will also make working with your genealogy software more pleasant because you will be working with its features, rather than against them.

Wouldn’t it be great if our genealogy software were trying this hard to cooperate with us!


  1. Greg says

    Helpful thanks. Often I've got an age of a person and then work back to a year, but without knowing a month, I am left uncertain as to the precise year. I've therefore guessed at the year and left a note in the event field about it. I'll now have to reconsider. I'd now appreciate hearing of some ways to keep a log and task lists.

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