William O'Callaghan

Lieutenant General William "Bull" O'Callaghan, BSD (; 3 July 1921 – 26 December 2015) was an Irish Army officer.

Early life O'Callaghan was born in Buttevant, County Cork, and joined the Irish Defence Forces at age 17 in 1939. with UNIFIL having suffered 145 combat casualties in its previous 4 years, 35 of them fatalities, O'Callaghan said: "Peacekeeping is not about firing shots. It's about not firing and stopping those who are. We must look for trouble at the 4 points of the compass, and then we look behind our backs."

Legacy Irish cadets in training compete for an award named in his honour; the "Lt Gen William Callaghan Sword" is awarded to the cadet who displays the best tactical ability.

Honours and awards Lieutenant General O'Callaghan was a recipient of the Distinguished Service Medal, and Lebanese National Order of the Cedar.