Four major land reforms have taken place in Romania: in 1864, 1921, 1945 and 1991. The first sought to undo the feudal structure that had persisted after the unification of the Danubian Principalities in 1859; the second, more drastic reform, tried to resolve lingering peasant discontent and create social harmony after the upheaval of World War I and extensive territorial expansion; the third, imposed by a mainly Communist government, did away with the remaining influence of the landed aristocracy but was itself soon undone by collectivisation (considered by some as yet another land reform), which the fourth then unravelled, leading to almost universal private ownership of land today.