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.

READ ALSO: What is Dia De Los Muertos? 5 Things to Know about the Day of the Dead

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:

All Saints039 Day 1
A woman visits the tombstone of a relative on All Saints Day in the cemetery of San Lorenzo in Ronda, near the southern Spanish city of Malaga, November 1, 2011. Catholics mark All Saints Day by visiting the cemeteries and graves of deceased relatives and friends. REUTERS
All Saints039 Day 3
A man kneels before a grave on All Saints Day in the cemetery of Derio near Bilbao November 1, 2011. Catholics mark All Saints Day by visiting the cemeteries and graves of deceased relatives and friends. REUTERS
All Saints039 Day 5
A woman kneels in front of a grave at the cemetry in the western Austrian village of Absam October 31, 2011. Catholics in Austria mark All Saints Day (Allerheiligen) on November 1 by visiting the graves of loved ones. REUTERS
All Saints039 Day 6
People paint a tombstone at the cemetery of Casabermeja, near the southern Spanish city of Malaga October 26, 2011. Catholics will mark All Saints Day on November 1 by visiting cemeteries and graves of deceased relatives and friends. REUTERS
All Saints039 Day 7
A woman looks at the crosses at the cemetery of the nameless (Friedhof der Namenlosen) in Vienna October 30, 2011. Catholics in Austria mark All Saints Day (Allerheiligen) on November 1 by visiting the graves of loved ones. REUTERS
All Saints 9
People pay their respects at the Olsany cemetery in Prague October 30, 2011. REUTERS
All Saints 10
A man sits in front of a grave in the Cemetery of Villanueva, on the outskirts of Guatemala City, October 31, 2011. Catholics will mark All Saints Day on November 1 by visiting cemeteries and graves of deceased relatives and friends. REUTERS
Religion