Veneration of Alban as Protomartyr of Britain depends on a cult of great antiquity at St Alban’s, known during the years of Roman occupation as Verulanium. Bede records in his Ecclesiastical History of the English Nation how, during a persecution by Diocletian, Alban surrendered himself in place of a Christian priest, and so unbaptised by water, attained a baptism of blood. In the same persecution Julius and Aaron, at Caerleon on Usk, are named among others who gave their lives for the faith.

Seventeen Irish Martyrs were put to death for the Catholic faith between 1579 and 1654 and were beatified in 1992. They include priests and lay people, men and women. Some were hanged, others were hanged, drawn and quartered. One or two died under torture. See the article in Wikipedia.