In the Novgorod Republic, the city posadnik was elected from among the boyars by the veche (public assembly). The elections were held annually. Novgorod boyars differed from boyars in other Rus' lands in that the category was not caste-like and that every rich merchant could reasonably hope to reach the rank of boyar. Valentin Yanin, the Soviet "dean" of medieval Novgorodian history, has found that most posadniks held the office consecutively for sometimes a decade or more and then often passed the office on to their sons or another close relative, indicating that the office was held within boyar clans and that the elections were not really "free and fair." Yanin's theory challenged historians' understanding of the Novgorod Republic, showing it to be a boyar republic with little or no democratic elements. It also showed the land-owning boyarstvo to be more powerful than the merchant and artisan classes, which until that time were thought to play a significant role in the political life of the city. It also called into question the true nature of the veche, which up until that time had been considered democratic by most scholars. Yanin's interpretation of the Novgorod government as an hereditary oligarchy is not universally accepted, however.