By forging a middle ground between the sedentary Slavic communities of the northern forests and the nomadic Turkic groups of the southern steppes, the Cossacks bridged a centuries-old ecological divide and facilitated a decisive shift in the balance of power between forest and steppe in the early modern period. Of Russia, but not necessarily Russian, Don Cossack freebooters advanced the cause of empire by contesting Ottoman control of the Black Sea region and facilitating the Russian conquest of vast expanses of Eurasia. When their world of frontier raiding and trading was replaced by a world of imperial boundaries in the early eighteenth century, the communities of the Don avoided extinction by embracing ethnic and juridical distinction. The Cossacks who survived the Russian reordering of the steppe re-invented themselves as servants of the Romanov dynasty, becoming imperial bodyguards and border guards, mountain men and mounted patrolmen.

The Don Cossacks were not a captive nation annexed by an aggressive empire, but a community created through the joint efforts of imperial officials and residents of a closing frontier. They represented a living legacy of the regional, dynastic, bureaucratic, and diplomatic forces that shaped Russian expansion. No nation-centered narrative can explain their experience. Their persistence in the imperial era resulted from the very fact that they seceded from a population category that was identified as “Russian” and synonymous with serfs, subjects, and powerless people. By 1739 Don Cossacks had closed their communities to Russians and codified their boundaries in record books and birth registers.