The extensive trade networks of the Ancient Maya contributed largely to the success of their civilization spanning three millennia. The Maya royals control and wide distribution of foreign and domestic commodities for both population sustenance and social affluence are hallmarks of the Maya visible throughout much of the iconography found in the archaeological record. In particular, moderately long distance trade of foreign commodities from the Caribbean and Gulf Coasts provided the larger inland Maya cities with the resources they needed to sustain settled population levels in the several thousands. Though the ruling class essentially controlled the trade economy, a middle merchant class supervised import and export from cities and trade ports. Not much is known of the Maya merchant class