The problems posed by the rigid political structure were doubled by social issues culminating in the 1907 Peasants' Revolt. The land reform under Domnitor Alexandru Ioan Cuza had only partly answered the pressure of a growing landless peasantry, and it was soon rendered largely ineffectual by the rapid population growth in the rural sphere, as well as by the intransigence of Conservatives towards further land grants. In addition, Romania's Old Kingdom (Moldavia and Wallachia) kept its traditional restrictions of civil rights for persons of religions other than Eastern Orthodox, which progressively (after selective integrations) applied only to Jews (until 1923); since such a regime implied than many professions were not accessible to the non-Orthodox, the excluded communities directed their efforts towards several niches, including leasehold estates that drew hostility from landless peasants who were generally underpaid for work provided (a source for the partially anti-semitic message of the 1907 revolt).