1 Euro John Paul I

John Paul I reigned for just 33 days in 1978 — the shortest pontificate of the 20th century — and died before a single coin bearing his likeness entered circulation. The Vatican's 2005 issue, part of the sede vacante and memorial series surrounding John Paul II's death, brought his image to coinage nearly three decades after his papacy ended. Whether his actual cause of death was cardiac arrest, as officially stated, remains disputed; no autopsy was ever performed.