There are countless local feast days scattered throughout the world that are only observed in certain countries or dioceses.
Among them is the feast of "Santi Pontefici Romani," on July 7, which honors all the popes who were ever canonized.
According to VaticanNews, "The feast brings together the memory of all of the [beatified and canonized] Roman Pontiffs: 82 saints and 9 blessed (to date in 2022). With this feast, celebrated in St. Peter's, we want to celebrate Peter's mission which continues in all his successors, some of whom have heroically witnessed the mandate to confirm the brothers, deserving to be registered in the register of saints and proposed to the veneration of the Christian people."
Only a small handful since 11th century
Larry Peterson wrote an article for Aleteia that provided more information on all the popes who have been canonized.
He mentions how a relatively few have been canonized in recent centuries:
Interestingly, of these 82 saints, only eight have been canonized since the 11th century. Regarding that number, we should remember that during the Church’s first 1,000 years, there was very little formal process in place for the canonization of a saint.
Those eight are:
Pope Benedict IX (#142); Pope Gregory VII (#156); Pope Gregory X (#193); Pope Pius V (#224); Pope Pius X (#256); Pope John XXII (#260); Pope John Paul II (#264); and Pope Paul VI (#262).
After the first millennium, the Church began to develop an orderly process for determining the qualifications of those presented for sainthood. On July 4, 973, Pope Benedict VI canonized Bishop Ulrich of Augsburg. St. Ulrich thus became the first person canonized by a pope.
One important fact to note is that, "The average waiting time for a person to be canonized after death has been around 180 years. Pope St. John Paul II was canonized just nine years after his death."
It may turn out that there are many more popes who were saints, but we will likely not know until we meet them someday in Heaven.
