[1] He was the second youngest son of Mary (née Murphy) and David O'Riordan and he was born in Effin, County Limerick, Ireland.
The Sierra Leone Civil War began in 1991 when the Revolutionary United Front attempted to overthrown Joseph Saidu Momoh, then president.
[2] He was an outspoken critic of the war and vociferously urged top officials in the military to put an end to the killing.
[2] In 2001, Bishop O'Riordan was award Sierra Leone's Commander of the Order of Rokel (COR), the country's highest honor for outstanding pastoral and humanitarian services.
[3] On 10 February 2017, the Diocese of Kenema invited clergy from across the nation to celebrate a memorial Mass in Bishop Johnny's honor.