Gibraltar-Vatican Joint Issue
The Vatican City State issued its first stamps in 1929, the same year that it was established under the Lateran Treaties. It released its first joint issue in 1969. Joint issues of stamps by the Vatican and other countries were uncommon for most of the twentieth century. In 2000, the Vatican and Poland released a joint issue designed by Czeslaw Slania which commemorated the eightieth birthday of John Paul II. However, the early twenty-first century saw a substantial increase in joint issues. In 2003, a set released by the Vatican and Poland celebrated the twenty-fifth anniversary of John Paul II's pontificate. The following year, a joint issue of the same countries commemorated the pope's return visits to Poland. In 2005, five of the eleven stamp sets released by the Vatican were joint issues. There have also been joint issues with Germany since Benedict XVI became Pope. In 2011, the Vatican and Croatia released a joint issue which commemorated the tercentenary of the birth of Rugerius Boscovich (1711 – 1787).
History of the papacy
When Germany invaded Poland on September 1, 1939, the Vatican declared neutrality to avoid being drawn into the conflict and also to avoid occupation by the Italian military. In 1944, the German Army occupied Rome. Adolf Hitler proclaimed that he would respect Vatican neutrality. However, several incidents, such as giving aid to downed Allied airmen, nearly caused Nazi Germany to invade the Vatican. Rome was liberated by the Allies after several months of occupation.