(literally, “an official” from the Greek diakonos), a director and clerk in the offices of various administrative departments in Russia until the 18th century. There were various kinds of d’iaki; they served the sovereign, powerful feudal lords (bishops’ and monastic d’iaki served ecclesiastical lords), the city veche (popular assembly), or the administrative offices of cities and the countryside.

During the period of feudal fragmentation, the majority of d’iaki who served princes were serfs. By the 15th century, however, they were landowners and many were petty feudal lords. D’iaki made up the ranks of the state administration. Highest ranking were those with places in the Duma, the dumnye d’iaki, who first appeared in the 16th century. The d’iaki administered the offices (d’iachie izby) of central (prikazy) and local administrative bodies; they were paid a salary for their service.

Gradually, a hereditary prikaz bureaucracy was formed. Its members owed their positions to the sovereign. Closely linked with the service gentry, it supported autocracy in its struggle with the boyar aristocracy. Included among the ranks of the d’iaki were the major statesmen A. F. Kuritsyn, I. M. Viskovatyi, A. Ia. Shchelkalov, V. D. Shchelkalov, A. Ivanov, and L. Ivanov.