If you know enough about your Irish family history, you probably know what county your ancestors originated from but if not it's a crucial piece in your genealogy puzzle.

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This is a really crucial piece of information – if you have a common last name, you’ll really be lost if you try to search the whole country of Ireland. It’s like trying to find a needle in a haystack.

But even if you know your ancestors’ county of origin, there’s more information you need to know if you want to trace your heritage even further back in time.

Once you find your ancestors in our Irish parish records (free to search forever), you’ll want to look in other databases that make use of Civil Registration Districts.

The good news is, it’s really easy to figure out what district your ancestors lived in if you have this map.

Civil registration districts

Some of the most important record sets for Irish genealogy are broken down by geographic areas called Civil Registration Districts. These districts were set up for record-keeping purposes.

Sometimes your family’s Civil Registration District will have the same name as the county, but most of the time it will be called something else – there are multiple civil registration districts in every county of Ireland.

To complicate things even further, some Civil Registration Districts span two counties. For instance, the Kilmallock district is mostly in County Limerick but also spills over the border into County Cork.

The map

FindMyPast's original map - pictured above or you can zoom in via this link - shows both county and Civil Registration Districts. The solid lines are counties and the dotted lines are the smaller Civil Registration Districts.

Once you locate your ancestors in our parish records, you’ll know more about their specific location by learning their parish. Locate it on a map and note its approximate location within the county.

Then, using this map, you should be able to easily cross-reference and see what Civil Registration District your ancestors were in.

Congratulations! You’re now armed with information that you’ll need to locate your ancestors in our other essential Irish records – the largest online collection of Irish records anywhere.

* This article was originally published in association with FindMyPast in 2017.