The Fenian movement (Irish Republican Brotherhood) was a secret society that attempted to achieve Irish independence through insurrection, such as the Easter Rising in 1916, when Britain was involved in World War One.
Editors. "Fenians arrested for planning uprising". The Literary Encyclopedia. First published 01 February 2010; last revised 30 November -1.
[http://www.litencyc.com/php/stopics.php?rec=true&UID=5088, accessed 21 April 2015.]