Imagine the Caribbean during the Golden Age of Piracy. Now replace the diversity of humans interacting with a diversity of animal races, each an artistic blend of a real animal species and a human culture who was present during this time, English, Spanish, Arawak, Mayan, Dutch, West African, etc.
These races will be player and GM created and should follow these guidelines.
1) They need to reflect accurately (and in a respectful manner) the historical and cultural realities of the group they represent. The animal species playing the role of the English should feel like the English in terms of their history, language, geography and culture. Small and interesting differences are fine and encouraged but they should not change the overall feel of the race to the point they no longer look like their historical analog. And remember that ethnic and cultural differences should trump national ones. For example, the Irish and English are both technically British, but they are culturally distinct and so should each get their own animal variant.
2) The animal chosen must be either native to the homeland of the group they portray or associated strongly with that group. For example, I would allow lions for the English because of their association with the English monarchy but not koala bears.
3) Animals should all be anthropic in nature. They must be at least capable of bipedal ambulation, possess opposable thumbs on at least their fore limbs, and be capable of complex verbal speech. Beyond that the species can be as humanoid or animal as you like.
As an example and template I will create the first of many.
Name: Aztec
Template Animal: Jaguar
Physical Description: Supremely adapted to their jungle homes, the Aztec are a bipedal feline race with a spotted and, rarely, black coat, sharp shredding foreclaws and stout hindclaws for climbing.
Culture and History: The Aztec rose to prominence deep within the Spanish-Main and their empire stretched across both oceans before the coming of the Europeans. Facing the superior firepower and deadly diseases of the invaders, that Empire has shrunken in recent decades, but thanks to their natural born strengths along with their knowledge of the native rainforests, they have hung on under the leadership of their God-King Montezuma the Fourth. Most Aztecs encountered along the Main or within the Caribean are either refugees from the wars with the Spanish, escaped slaves, or guerilla fighters come to fight on behalf of the Caribbean natives, the Arawak and their Maroon allies. Elite among their people's warriors are the ocelotl who practice secret martial arts and rituals culminating in the replacement of their organic foreclaws with razor sharp Obsidian prosthetics. It is largely thanks to the dreadful predadory skills of these warriors that the Spanish have been prevented from subsuming the whole of their rich empire. The Aztecs are hated by the Europeans not only due to their successful resistance, but their practice of sacrifice (and, it is rumored, cannibalism) which the Europeans find abhorrent. Although in reality the practice has waned in recent years and not all Aztecs approve of these blood rituals, their existence has tainted the entire people in the minds of the westerners. As for cannibalism, the Aztecs are natural predators, but most consider the eating of other sentient animals (therians) to be taboo, even those who support the old ways, for the gift of therian blood is for the Gods alone, not mortals, to possess.
I will accept races on the basis of quality so that it's not just a first come/first serve free for all.
As for the game itself it will focus on a single group of pirates (or privateers depending on your perspective) who are a motley assemblage of various species and cultures. It will be player driven and set in an open world to simulate the freedom of the open ocean and the buccaneer lifestyle.
General Concepts
Unless contradicted with good reason, the following general principles about the world and Therians will hold
1) All Therians are intelligent and vary as individuals not species. This is in place to prevent overt racist crap since these species are reflections of human ethnicities and cultures.
2) The flow of history is analogous to our own and religions, people and nations present in our world will all be present in this world.
3) All therians have a favored diet based on their animal lineage but they are all also capable of being omnivorous when necessity demands. A Lion may prefer mutton, but he can survive on bread and cheese <YUCK!>
4) The issue of disease is less a factor due to the high biological diversity between peoples which resists the spread of pathogens. Outbreaks of plague and rabies did deal a blow to natives but nothing comparable to that which small pox did in our own world.
5) Mating between different species is a taboo in some societies, outlawed in others, and used as a genocidal weapon by others. When it occurs, the offspring inherit either the mother's or the father's thera or animal soul. Other factors like personality and intelligence may blend, but the animal characteristics come wholly from one parent or the other at random.
6) Although some Therians may seem the natural predators of others, eating sentient species is still considered cannibalism and is a taboo in almost every society. None the less there are famous instances of criminals, outlaws and even rulers giving into their baser instincts.
7) Historical figures in our world will exist also in this one. Keep this in mind when designing your race. If you are designing the English then Blackbeard will be of that species (so it would help if it had something that could be conflated with a beard [like a mane]).
8) The date will be the early 1700s at the close of Queen Anne's war which in this world has seen a tenuous alliance between the Brittish privateers and mainland natives for they share the same enemy in the Spanish.