The 40-year-old woman had been stabbed to death, Italian newspapers reported on Sunday, but they also said that the woman had been dead for two days before her body was found.
She was not killed on the motorway, but her body had been dumped next to the road not far from the town of Cosenza.
Detectives have told Turin-based newspaper La Stampa that the woman, named only as Petra S., had a surprising amount of personal documentation with her.
The handbag found with her body contained not only a purse with money in it, but also bank documents, savings books, credit cards and a number of letters written to people in Germany.
The Italian police have released a photograph of the woman in an appeal for information.