There are more than holidays of one's country that people celebrate, often there are annual celebrations associated with a family or communal event from long ago. The coming of that day would remind your character of home and honoring it would be somewhat an obligation.
Perhaps this exercise will help build the holiday that your toon and their family/clan/village celebrates. The options are numbered if you wish to use a d6 or you can come up with your own.
I. This day celebrates...
1. a fallen hero
2. a supernatural being
3. the harvest
4. a time of mourning/loss/shame
5. the founding of the clan/village
6. a great kindness/miracle
II. ... with ...
1. a feast
2. a sacrifice
3. a dance
4. an intimate ritual
5. a contest
6. an artifact or totem
III. ... but ...
1. everyone must tell a story
2. it requires expensive materials
3. it requires a pilgrimage to a specific place
4. you have to hunt a specific beast
5. it requires a mating ritual
6. people have to dress in a particular way
IV. And if you don't celebrate it, then ...
1. you will be hunted by supernatural beings.
2. you will be considered unclean and must be religiously cleansed.
3. you will be cursed with bad lick.
4. you will be overcome supernaturally by an emotion, ie. rage or depression.
5. you will be banished by your house, clan, or village.
6. you will be haunted by your ancestors.
V. Choose a name that best represents your toon's culture and its purpose.
VI. The celebration happens ...
1. on a specific date.
2. during specific phases of the moons.
3. during an eclipse, solar or lunar.
4. at the changing from one season to the next.
5. when a specific celestial event happens, ie. when a constellation is dominant in the sky.
6. when a particular activity unique to the clan or village has been completed.
With so many social RP events that happen during the course of the year, a coming celebration associated with your character's clan or village would be a nice addition to the conversation and give others an opportunity to learn a little something about the character and their past.
NEXT TIME - RP Character Building Idea: Five Lessons Learned