Imperial holy days
Life on Terra, during pre-imperial antiquity, centered on the military, agriculture, and industry. The short, cold days of winter would halt most forms of work. Brumalia was a festival celebrated during this dark, interludal period. It was pre-Imperial in character and associated with crops, of which seeds are sown in the ground before sprouting.
People would sacrifice cattle to a deity erased from historical records. Vine-growers would sacrifice ptera-squirrels in honor of It—for the ptera-squirrel is an enemy of the vine; and they would skin them, fill the skin-bags with air and jump on them. Civic officials would bring offerings of first-fruits (including wine, oil, grain, and honey) to the priests.
Although Brumalia was still celebrated as late as the 36th millenia, it was uncommon and celebrants were ostracized by the Ecclesiarhy (Sect: Temple of the Saviour-God). However, some practices did persist as scattered traditions on fringes of the Imperium, especially in worlds infested by ptera-squirrels.
Candlemass: Which marks the end of the year. Song sung during candlemass: Holy triumph of the golden throne
The Day of Ascension: Marking the Emperor’s enthronement upon the Golden Throne
Emperor’s Day: Which heralds beginning of the new year and celebrates the Emperor’s benevolence and divinity.
Feast of the Emperor’s Ascension: This is the day when the Ascension of the Emperor to the Golden Throne and His apotheosis is celebrated. This holy day is celebrated with much feasting in the Emperor’s honor along with prayer for forgiveness of sins and trespasses against Him on December 1st of each year. If the Imperium is ever in a state of war it will always seek a cease-fire on this holy day to properly observe the Feast of the Emperor’s Ascension.
Martyrs’ Day: On this day the Imperium remembers all those who have fallen in the Emperor’s Service and to vow that their deaths shall not have been in vain. This takes place on May 31st of each year. It is honored by Imperial forces seeking out and destroying many heretics and mutants in commemoration of the losses the Imperium has suffered over time while seeking to cleanse the shame of defeat with the blood of the Emperor’s foes.
Saints popular at Koronus Expanse
Saint Drusus, main Saint of Calixis sector
Saint Cognatius, Saint of Koronus expanse, Converted many worlds in the Koronus Expanse to the Imperial Creed. Rogue Trader: Faith and Coin pg. 7
Saint Asceline, Saint of the Calixis Sector, local patron saint of Explorers and those who crusade into the unknown.
Lost Pilgrim, Saint of void travelers, does not have official holy day but is often honored at the beginning of perilous star voyages or pilgrimages.
Saint Brannicus, He is said to have beaten three hundred sinners to death with his severed leg which remained miraculously intact. Honored among Imperial Guardsmen
Source edited for Ultina Tectum campaign
Development of Imperial Doctrine of Faith
The Emperor’s Prayer
Our Emperor, who art on the throne,
hallowed be thy Name,
thy Imperium come,
thy will be done,
across worlds as it is on Terra.
Give us this day fulfillment of our holy duty.
And don’t forgive us for our trespasses,
as we do not forgive those
who trespass against you.
And lead us to victory,
and deliver us from evil.
For thine is the galaxy,
and the power, and the glory,
for ever and ever.