Many things are named in honor of popes, including shrines, schools and other structures. In Singapore, there's even an orchid variety with a papal moniker: Dendrobium His Holiness Pope Francis, ...

This week is significant, for religious reasons it has not always existed. It was in 1582, Pope Gregory XIII instituted a major reform of the calendar, which has since been almost universally adopted.

Many things are named in honor of popes, including shrines, schools and other structures. In Singapore, there's even an orchid variety with a papal moniker: Dendrobium His Holiness Pope Francis, ...