Taking as a starting point some of my previous researches (Preda Bodoc 2015 and Preda Bodoc, Ardeleanu Gomoescu 2016), the present paper represents a small contribution to the current diachronic research by analyzing all the complex sentences in which cum was involved either as a simple connector, or as an element of a compound. So, based on a corpus of Old Romanian texts, covering the period 1500-1640, the primary objective of the article is to bring evidence for the multifunctional status of the simple sentence connective cum ‘that/as’ (used as a complementizer, a relative, a relative-interrogative, or as a subordinator), and also for the heterogeneity of the structures constructed with this element (complex complementizers: cum că ‘that’, cum să ‘so that’, and prepositional structures: de cum ‘about how’, pe cum/precum ‘that/as’, pănă în atîta cum ‘so that’ etc.). Most of these complex connectors have been replaced or disappeared from the Present-day Romanian, and this is why we need to go back in time, and to follow the grammaticalization process of these adverbs (cum and oricum), as they become complementizers, subordinators, and, finally, expletives or discourse markers. Some of the formal observations have been confronted and confirmed by the quantitative analyses of the corpus. In the end, I believe that, by clarifying the use and the evolution of this element, it’s frequency and variability, the present study may provide valuable insights into the proper characterization of the inventory of sentence connectors, but also into the historical development of the Romanian language.