To mark St Patrick's Day 2017, the genealogy website Findmypast has opened up its Irish records to the public for free.

Until 11.59pm on 17 March, you can get free access to all sorts of records – from WW1 to the Easter Rising to migration documents – and trace your Irish ancestry.

The Irish diaspora across the world is huge. It is spread far and wide, but there is a sizeable Irish heritage population in the US in particular, a consequence of the catastrophic Irish Potato Famine in the mid-19th century.

A million people died and a further 1.5 million emigrated during the famine, reducing Ireland's population by around a quarter.

Findmypast has millions of Irish records. It has over 30 million Irish birth, marriage, death and parish records and more than 24 million records regarding the Irish moving around the world.

Every other person seems to make some claim to Irish ancestry, especially around St Patrick's Day. Now's your chance to check for free on Findmypast if you really do have some Irish blood.

In 2017, St Patrick's Day falls on 17 March.