The late 19th century witnessed major land reform, spearheaded by the Land League under Michael Davitt demanding what became known as the 3 Fs; Fair rent, free sale, fixity of tenure. Parliament passed laws in 1870, 1881, 1903 and 1909 that enabled most tenant farmers to purchase their lands, and lowered the rents of the others.[34] From 1870 and as a result of the Land War agitations and subsequent Plan of Campaign of the 1880s, various British governments introduced a series of Irish Land Acts. William O'Brien played a leading role in the 1902 Land Conference to pave the way for the most advanced social legislation in Ireland since the Union, the Wyndham Land Purchase Act of 1903.