On Nov. 1, Christian families across the globe gathered together to celebrate All Saints' Day. The feast day, also known as All Hallows' Day or Hallowmas, is celebrated one day after All Hallows' Eve (Oct. 31). It's an opportunity for Anglicans and Roman Catholics to remember all saints and martyrs, known and unknown, throughout Christian history.

In honoring the day of obligation, believers are required to attend church and try to abstain from any servile work.

The tradition of remembering saints and martyrs and dedicating a specific day to them each year has been around since the 4th century. However, it wasn't until 609AD that Pope Boniface IV decided to remember all martyrs.

Initially, May 13 was set aside as the Feast of All Holy Martyrs. Then in 837AD, Pope Gregory IV extended the festival to a remembrance of all saints, altered the name to Feast of All Saints, and changed the date to Nov. 1.

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Today the holiday is celebrated by Catholic and Anglican communities at cemetaries around the world.

Here's a look at All Saints' Day celebrations from Spain to the Philippines: