Juan Diaz Canales and Juanjo Guarnido's Blacksad is set in the USA of the 1950s and tells era-appropriate tales of John Blacksad, a private investigator. Blacksad is a black-furred humanoid cat. Of course, all the roles in Blacksad are portrayed by humanoid animals. Blacksad's adventures pit him against corrupt businessmen, racist ideologues and the atomic scare. As I said, it's era-appropriate.
Blacksad's creators make excellent use of the various animal types who comprise their cast - it's about more than just interesting visuals. In one story, Blacksad is apprehensive at following a rat down an alleyway. The reader understands his apprehension because the man is a rat. It's a great storytelling shorthand.
On the left you see the police car; on the right you see the policeman. Nothing more needs to said here, the following panel depicts Blacksad in the local jail. After reading so many North American comics which seem to adhere to the "shoot everything!" edict, it's always refreshing to find creators who know which details matter to the story. The wheres and hows of Blacksad's arrest don't actually matter and they know it. This is a briskly-paced action-packed mystery story, there's no space to slow down the narrative.
Another great element to Blacksad is the story dealing with racism; various white-furred animals begin cracking down on black-furred animals, which means Blacksad himself isn't safe, regardless of the colour of his muzzle.
(Although if there was World War II in Blacksad's world - and it seems that there was, based on various comments - would Nazi-like stormtroopers really fly in 1950s USA? Shouldn't they be Klansmen?)
Stan Sakai's Usagi Yojimbo is set in Feudal Japan and relays tales of the wandering samurai Miyamoto Usagi. Usagi is a humanoid white-furred rabbit. Sometimes Usagi's tales touch upon real historical events, aspects of then-relevant Japanese culture or Japanese folklore. Unlike Blacksad, there are occasional efforts at breaking the fourth wall and observing how Usagi's version of Japan doesn't quite hold up.
(You probably recognize the Teenage Mutant Ninja Turtles above; Usagi is a separate intellectual property, but has been so closely associated with the Turtles during his publishing career that he's probably still most widely-known as a character from their lines of action figures and cartoon programs, rather than the star of his own unrelated comics books.)
It's amazing that there are still so many stories which can be told with Usagi after all of these years and it's a credit to Sakai that the current adventures remain vibrant. Usagi's excellent supporting cast, comprising characters like the rascally rhino bounty hunter Gen, tragic blind swordspig Ino and ever-replenishing ranks of the Neko Ninja, together make great foils for Usagi (and by the way, Usagi Yojimbo Book 4? Where all the aforementioned characters join forces? So good.).
Usagi does seem to have become slimmer over the decades - a thinner face, a less stocky build. The fur on the sides of his head has also become looser, more scruffy.
Blacksad was recently collected as a hardcover by Dark Horse, but apparently there are still new stories being published in France; hopefully Dark Horse will supply translated copies in the future.
Usagi Yojimbo is published almost every month by Dark Horse; there are now more than 20 volumes collected into trade paperbacks, but you can start reading the series almost anywhere; many issues are stand-alone tales and the trades always seem to complete story arcs.