Welsh-titled peers derive their titles from a variety of sources. After Llywelyn ap Gruffudd of the House of Aberffraw, the last Welsh Prince of Wales, was killed during the Edwardian Conquest in 1282, the Principality of Wales was divided into English-style counties. Many of the former native titles were abolished, but some of the native Welsh lords were given English titles in exchange for their loyalty. Welsh Law remained in force in the Principality for civil cases, including for inheritance. However, Edward I did reform Welsh succession to introduce male preference primogeniture, a reform which facilitated the inheritance by English marcher lords of Welsh lands.