(CNN)Every year on November 1, many Roman Catholics and other Christians around the world observe All Saints Day, which honors all saints of the church that have attained heaven. In the Eastern Orthodox Church, All Saints Day is observed on the first Sunday after Pentecost. Here's a look at the history and traditions of this holy holiday.
All Saints Day: The history and traditions behind the holiday
Although now observed in November, All Saints Day was originally celebrated on May 13, although the origin cannot be traced with certainty, accoring to Encyclopedia Brittanica. Pope Boniface IV formally started what would later be known as All Saints Day on May 13 in 609 AD when he dedicated the Pantheon in Rome as a church in honor of the Virgin Mary and all martyrs.
The current date of November 1 was established by Pope Gregory III during his reign (731-741 AD) when he dedicated a chapel in Rome's St. Peter's Basilica in honor of all saints. While this celebration was originally limited to Rome, later in 837 Pope Gregory IV ordered the official observance of All Saints Day every November 1 and extended its celebration to the entire Church.
While many canonized saints are celebrated with their own individual day (such as St. Patrick), saints that have not been canonized have no particular holiday. All Saints Day recognizes those whose have attained heaven, but their sainthood is known only to God. Even so, Catholic observances tend to focus on known saints, those canonized by the Catholic Church.
According to Catholic Online, within the Catholic Church, All Saints' Day is generally considered a Holy Day of Obligation, meaning all Catholics must attend Mass unless they are prevented by illness or another sufficient excuse. After the Protestant Reformation, many Protestant sects kept All Saints Day. Methodists, for example, acknowledge it as a day of giving God earnest gratitude for the lives and deaths of saints, according to Christianity.com.
Although not a public holiday in the US, All Saints' Day is observed publicly in many countries. In France and Germany, people have the work day off and businesses are closed. In the Philippines, All Saints Day is known as "Undas" and isn't just for remembering the saints, but for honoring and paying respects to departed loved ones, usually with prayers, flowers, and good offerings and graves.