As you can see, the composition of Manet's is hardly original. In fact, is was a direct tribute to  Titian's Venus of Urbino (1538-39) and indirectly to Giorgione's Venus Asleep (1510). Titian himself, was paying tribute to Giorgione some 20 years after Giorgione's painting. And Ingres' Odalisque with a Slave (1840) pre-dates Manet's by some 25 years.  

Why was Olympia such a scandal? 

In Ingres case, the difference is that he set his painting in an exotic land of the near-east, far from the sensibilities of Europe. The painting is more other-worldly or romanticized (see Romanticism) closer to the nymphs and goddesses that the bourgeois loved to view and didn't, I believe, receive near the criticism (if at all) that Manet endured. 

 
Alexandré Cabanel (French)  
The Birth of Venus, 1863  
same year as Manet's Olympia  
typical classical composition  

Manet's painting compared to Titian's Venus of Urbino is the same -- not in copy, but in kind. Both subjects are laying languidly on their beds.  One is holding a flower the other has it in her hair.  Each has their left leg crossed. In Manet's case there is a black cat on the bed (the jpeg doesn't show it well), in Titian's there is a dog curled up and sleeping. The clothed attendants in the background tell us we're intruding into their private boudoir. The bed and pillows are almost identical in ruffled and slept condition, as is Giorgione's Venus Asleep, as is Ingres' Odalisque with a Slave. All the paintings are voyeuristic, yet Titian has his subject in the know of being watched -- looking directly at the viewer.  Manet's tribute is different only in his subject's disposition which is not the least bit shy of our attention.  

Notes 

 
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