Your characters begin as children age 5-14 who have been rounded up from throughout Mythic Europe. You could be from anywhere and any background, rich or poor, smart or stupid; the only requirement is that you have the Gift.
It is March in the year 1205; elder, powerful magi from the Greater Alps Tribunal are in the market for apprentices, and you have all been brought to Vienna where you will be presented to the masters for selection.
You probably didn't have any say in any of this.
Required Virtues: You must have the Gift.
Prohibited Virtues: You cannot take any Virtue which grants experience points, like Skilled Parens or Educated. Also, avoid Virtues which specific Houses get for free: Self-Confident; Hermetic Prestige; or Puissant Magic Theory, Intrigue, Creo, Ignem, Muto or Perdo. If you wanted Puissant, consider an Affinity instead. If one of those Virtues is so important to your character that you cannot imagine him without it, pick the House where you get it for free.
Inherited Virtues and Flaws: You will probably want to select Hermetic Virtues and Flaws which your character technically doesn't have yet, because you are only an apprentice. Go ahead and select them, marking them as (Inherited). These Virtues and Flaws will manifest as your character matures.
Other Virtue and Flaw Guidelines: Please follow the guidelines on p. 37 of Ars Magica 5th edition: no more than 5 Minor Flaws, no more than 1 Story Flaw, no more than 2 Personality Flaws, one of which can be Major. No more than 1 Major Hermetic Virtue and at least 1 Hermetic Flaw. Flaws especially can change during play; you will have opportunity to adjust your sheet as time goes by.
Major Hermetic Virtues: To help you pick a Major Virtue, I've briefly summarized all available Major Virtues from all the published books. I'm asking that PCs not duplicate.
Age: Most apprentices begin their training at age 8-10, and this is the suggested starting age for PCs. However, you might be as young as 5 or as old as 14. Youth modifies all your attributes as well as your Size. In addition, there are special Virtues and Flaws only allowed to children under age 14; these Virtues and Flaws are swapped out for others as the child matures. Especially young characters are weaker than older ones, and so making this suboptimal choice earn you Fans (Fans are explained below under House Rules).
Early Education: While it is not expected or common, you might have gotten some education in Academic Abilities prior to your apprenticeship. You must have a character story that explains how you got entry to a parish, cathedral, monastic or municipal school, or how you afforded a private tutor, prior to play. Ordinarily, you would represent this with the Educated virtue, but because that virtue grants experience points, you cannot take it. Instead, you must have a Story Flaw such as Black Sheep, Close Family Ties, Favors, Heir, Hermetic Patron, Mentor, Monastic Vows, or Patron.
Supernatural Abilities: It is common, though not universal, for children with the Gift to possess a Supernatural Ability. When you begin your training, your master will transform that ability into the talent for working Hermetic magic. In rare cases, the Supernatural Ability is preserved. If you want to keep a Supernatural Ability from childhood, buy it as a Supernatural Virtue. Otherwise, you do not have to buy the Ability. Your character will lose it when he or she becomes an apprentice. The Supernatural Ability your character had before becoming an apprentice, if any, and its loss or preservation, may be important to your vision of the character moving forward
Children with the Gift: As a reminder, life as a Gifted child is very hard. You were not allowed to play with other children, not that you had friends to begin with. When anything bad happened, you were inevitably blamed. Even your parents looked upon you with resentment and suspicion. Only children with the Gentle Gift had a healthy, happy childhood. Children with Blatant Gift are usually abandoned by their parents, and are lucky to be alive.
House: You, the player, can decide what House your character will join, or you can just make your apprentice and let the story go as it goes. This second choice -- placing your choice of House in the hands of the GM and the NPCs -- earns you Fans (again, see House Rules for Fans). Either way, your character is ignorant of what you, the player, has decided.
Apprentices is a book for Ars Magica that includes a lot of options and rules for playing characters like yours, including cantations, Child Virtues and Flaws, and the attribute modifiers for youth. It is not required. You can totally make your character using only the rules in Ars Magica 5th edition. I have Apprentices, and if there is something in there which seems a good fit for your character -- like a Child Virtue or Flaw -- I'll propose it to you and you can decide for yourself.
No. The covenants of the Greater Alps are linked by magical methods of travel so it is comparatively easy for me to get all of you together, especially when I only have to do so once a year.
Magi in the Greater Alps like to say "this is how the Order of Hermes should be," which means that it is peaceful, rich in magical resources, and designed to let older magi do whatever they want. Basically, the magi here leave everyone else alone and expect the same in return. Their culture is extremely conservative; they wear Roman dress, use Roman titles, and call themselves Romans. Magi here spend a lot of time in their labs. There are more Archmages in the Greater Alps than any other Tribunal. It is worth noting that two Houses of the Order are based here: Criamon (in the Cave of Twisting Shadows) and Jerbiton (at Valnastium), but with a population of about a hundred magi, most very old and powerful, all the Houses are represented. Because of ancient prejudice, House Tremere is the least represented.
The Alps are home to many languages, including German, Italian, French and Occitan. However, I don't want to penalize your characters by forcing you to learn multiple languages just to talk to the locals. With a little hand-waving, I've decided to use German for most covenfolk in the Tribunal, and if you want to talk to non-magi, that is the language you will need.