The evolution of local cases and their grammatical equivalent in Greek and Latin

The Indo-European languages attest to a pie system with three local cases: locative, ablative, and (allative) accusative. I will focus on the system of local cases in Ancient Greek and in Latin. Both languages have a reduced number of case distinctions with respect to the pie system; in the field of spatial relations, they display interesting differences. In Ancient Greek the locative has merged with the dative, the ablative has merged with the genitive, and the accusative is retained as such. The three cases can be reinforced with all types of nouns with three different prepositions, en, ek, and eis and express basic spatial relations. Thus, a connection continues to exist between cases and spatial semantic roles, as shown by the fact that a fourth preposition, pará, could take all three cases and express adessive, ablative, and allative meanings. In Latin the locative and the ablative merged; as a result, location and source could no longer be distinguished through case marking alone. Some toponyms retained the locative case until the end of the Classical period. Consequently, Latin displays a sub-system with three case distinctions for this group of toponyms. Within prepositional phrases, only two cases occur in Latin, i.e., the ablative and the accusative. Source is expressed through the ablative with a special set of prepositions, while location and direction are both expressed with the same set of prepositions. Consequently cases became increasingly disconnected from the semantic roles they used to express.