Generally, almost all of the standard DD5 character classes will be allowed to play in the Petronia Game Setting. These include:
Cleric
Druid
Fighter
Ranger
Rogue
Wizard
DM permission is needed to play:
Barbarian - no local barbarian tribes.
Bard - restrictions on College of Lore
Paladins - restrictions on religion, gender, etc.
Monk - no local schools
Warlock - requires theurgism skill, which is difficult locally.
Restricted classes are limited to no more than 3 of that class in the game.
The following classes are not allowed:
Sorcerer
Some additional class considerations and notes follow ...
There are no barbarian tribes anywhere near the game setting. While you might be allowed to play this class, it will mean that you have wandered VERY far from home. Confer with the DM to determine clan, background, etc.
To some extent, Bards go where civilization supports them. Petronia is not quite on the high side of culture, so Bards played will be of the roaming minstrel type. The closest College of Lore is in in the cit of Willamantix, in the Mernian Empire. That places some limits on Lore advancement. There are no restrictions on College of Valor, however.
Religion is an important part of the Nolaria Campaign. If you are playing a human cleric, please align your Divine Domain with one of the gods listed below:
Knowledge: DelhariaRD, the Ur-principleRD.
Life: HelminaRD, OmiRD
Light: Rhamon, Simka
Nature: Flora, Du, Gaia
Tempest: Forlat
Trickery: Loki
War: Mares
Evil/Undead: GhakRD
If you are running a non-human or half-human, then one of the gods/goddesses from DDed5 is likely to be acceptable. Please coordinated with the DM.
The RD designation indicates that these gods/religion may grant raise dead.
There are several flavors of druidism practiced in the greater Nolaria Campaign. The one practiced in this area is Duism (the old god Du), which has a rather interesting connection to the Nolar Gods worshiped by the Mernians. The nemesis of Du is Gront, the God of the Earth. Both the Circle of the Land and Circle of the Moon may be chosen on reaching 2nd level.
Any of the Martial Archetypes may be played, though Eldrich Knight requires DM permission. If you choose Battlemaster, you likely started in one of the bigger cities such as Germedian.
Currently, there are no schools or temples in the Petronia area that train monks. There are such places in other parts of the world, so it may be possible to play a monk that has wandered far from his or her origins. This is likely to result in training and advancement difficulties.
If you choose the Oath of Devotion, the God of Justice is Tempar, though Zutin (the Kind of the Gods) may be used also). If you choose the Oath of the Ancients, Du is the god of Druids. Paladins will be expected to act strictly in character and focus on a chosen quest. Virtually all paladins are associated with a religion in the Nolaria Campaign. Many impose gender restrictions.
Given the mountainous terrain of Petronia, the Ranger class is a natural. Backgrounds of mountain man, farmer, hunter, woodsman could all lead a young person to embrace life as a Ranger. Both Hunter and Beast Master archetypes are allowed.
Rogues are fully allowed. All of the archetypes are allowed, including Thief, Assassin, and Arcane Trickster.
While warlocks are allowed in the Petronia game setting, attracting an otherworldly patron requires the study of theurgism. There are very few (and quite secret) mages in the Petronia area who are skilled at negotiating with higher order beings (theurgism) and most are unwilling to share that knowledge. That makes starting a warlock character difficult, though not impossible. Other patrons besides the Archfey and Great Fiend are possible but can only be discovered through study, research, and training in forbidden knowledge.
Wizards are fully allowed in game play. There are some schools of wizardry in Willamantix and Germedian. Local wizards may also provide some training. Depending on which Arcane Tradition your wizard decides to follow, you may have access to deeper knowledge in the form of class specialization:
Abjuration - advanced wards, exorcism
Conjuration - summon demons and angels
Divination - knowledge collection, magic analysis
Enchantment - materials
Evocation - combat magic, wild magic
Illusion - shadow magic
Necromancy - create undead
Transmutation - construction magic, alchemy
All schools have access to cabbalism and artificing if skill requirements are met.