Using the 1901/1911 censuses

Arguably the most accessible and widely-used resources for contemporary family research are the 1901 and 1911 censuses.

While fairly straightforward to use, I meet so many people who tell me that they were unable to find their ancestors on either census, and are at the brink of accepting that they must be descended from a long line of secret agents using pseudonyms and aliases.

However, this is almost never the case. The census pages are full of mistakes, while the online transcriptions often fall victim to human error.

So, let me offer some tips that I have learned and which may help you on your journey:

• Switch the surnames and forenames. As I mentioned, human error is always a possibility, and it is very easy for a National Archives volunteer to put 'John' where it should have been 'Smith' and vice versa. This was the trick that revealed the entry for my three-times great-grandmother Margaret Campbell on the 1911 census:

• 'Browse' it, don't 'Search' it. I imagine that most people click on 'Search Census' when carrying out a look-up, but personally I find the 'Browse Census' facility to be much more helpful in locating the extended family and learning more about the environment in which a person lived. I learned the value of this when I tired of searching for variant spellings of common names and was still winding up with hundred of incorrect results. If you are not getting anywhere by entering the name, then narrow it down by County and DED (District Electoral Division.) Open up each of the Townlands in a separate tab, and then you can start zeroing in on the households. The beauty of this type of search is that it lists all of the neighbours. So, those witnesses on your great-grandparents' marriage certificate? The older siblings you didn't know about? They all become much easier to locate because, while surname spellings and ages might throw you off on the 'Search Census' page, geographical tools will rarely throw you off.

• Extenuating circumstances. If you are still stuck and cannot find an ancestor in the 1901 or 1911 census, then there may be a simple explanation: he or she was not in Ireland. This does not mean that they had emigrated or that something dire had occurred; remember, the census simple reflects who was living where on one single night once a decade. So, male relatives could have been in military service with their wives/children having relocated along with them. If this was the case, then you might find them in the UK censuses. If you don't but suspect that they did serve in the military, then try looking for their records on Ancestry.co.uk's Military collection. If the record states that an individual was serving overseas in March 1901 or April 1911, then they are not going to be in any UK census.

The record that explained why an ancestor of mine was nowhere to be found in the 1901 census.

Sometimes, you get lucky with an ancestor who had a very particular name or profession that makes him or her easier to track down on the census. But for most people, the census is the first place they look when they start researching their families, and it is very easy to get lost, go wrong, or give up altogether.

If you find yourself getting stuck using the census, then drop me a comment and I'll be happy to try to help.

Who knows? Maybe your ancestor was one of the ones with pseudonyms and aliases...