Romans aren't the outlier here. Most ancient civilizations had a similar level of accomplishment; a one or two outstanding mathematicians every century, a few practical applications, some new rules of thumb. We did have a dark age, after the Romans after all, which likewise produced little (not none) new math.<p>The question should rather be, what made the Greeks (and, later, others who adopted their deductive, axiomatic method) so exceptionally productive at mathematics?<p>Or to paraphrase Wigner, why is Hellenistic mathematics so unreasonably effective?