J. Kahk graduated from Tartu University in 1951, postgraduated from Leningrad University, become Doctor of History in 1963 in Leningrad. He has studied the agrarian history of Estonia, from 1965 onwards has been dealing with mathematical methods in historical research.

Some problems analysed in this book:

• geographical «shifts» in agricultural production during the transition period;
• the character of cycles of agricultural production in the period of feudalism;
• the «immobile reserve» of labour force in the corvée system;
• the paradox of inefficency of manor economy based on corvée;
• the controversy of subjective and objective aims of class stuggle between peasants and nobility;
• the «splitting up» of peasantry and the birth of bourgeois society.