When Prince Nikolaus Wilhelm died in 1905, his nephew
Grand Duke William IV of Luxembourg (or Guillaume IV) became the last
dynastic male of the
House of Nassau (after 2 months). If Nikolaus Wilhelm's children had been deemed dynastic, then his son Georg Nikolaus, Count of Merenberg would have succeeded as Head of the
House of Nassau upon William IV's death. Georg Nikolaus would have thus become the reigning
Grand Duke of Luxembourg. However, his morganatic birth was deemed insurmountable, despite the fact that he had married a daughter of Tsar
Alexander II of Russia. In 1907, William IV, obtained passage of a law in Luxembourg confirming the exclusion of the Merenbergs from succession to the grand ducal throne. Georg Nikolaus's protests against the Luxembourg
Diet's confirmation of the succession rights of William IV's daughter,
Princess Marie-Adélaïde, were expected to be taken up by the Netherlands and by the
Great Powers which had guaranteed Luxembourg's neutrality in 1867. Nonetheless, Marie-Adélaïde did succeed her father, to become Luxembourg's first female monarch, in 1912. In 1919 she, in turn, abdicated in favour of her sister
Charlotte, whose descendants have reigned over Luxembourg since then. The heads of the house of Merenberg after 1912 were: • Georg Nikolaus (1912–48) • Georg Michael Alexander (1948–65) ==References==