Background
Wilhelm was born at Herleshausen, Hesse-Nassau, Germany, eldest child of Prince Wilhelm of Hesse-Philippsthal-Barchfeld (1905–1942), (son of Chlodwig, Landgrave of Hesse-Philippsthal-Barchfeld and Princess Caroline of Solms-Hohensolms-Lich) and his wife, Princess Marianne of Prussia (1913–1983), (daughter of Prince Friedrich Wilhelm of Prussia and Princess Agatha of Hohenlohe-Schillingsfürst). Through his mother he is descended from King Frederick William III of Prussia and King William I of the Netherlands.
Career
These two landgraviates were annexed by Prussia in 1866. The main branch (Hesse-Philippsthal) became extinct in the male line in 1925, thus making the Barchfeld branch the only surviving one of the Hesse-Philippsthal line. Gilbert I, Count of the Maasgau, daughter
842 Gilbert II, Count of the Maasgau, 825–875 Reginar, Duke of Lorraine, 850–915 Reginar II, Count of Hainaut, 890–932 Reginar III, Count of Hainaut, 920–973 Lambert I, Count of Leuven, 950–1015 Lambert II, Count of Leuven, daughter
1054 Henry II, Count of Leuven, 1020–1078 Godfrey I, Count of Leuven, 1060–1139 Godfrey II, Count of Leuven, 1110–1142 Godfrey III, Count of Leuven, 1140–1190 Henry I, Duke of Brabant, 1165–1235 Henry II, Duke of Brabant, 1207–1248 Henry I, Landgrave of Hesse, 1244–1308 Otto I, Landgrave of Hesse, 1272–1328 Louis the Junker of Hesse, 1305–1345 Hermann II, Landgrave of Hesse, 1341–1413 Louis I, Landgrave of Hesse, 1402–1458 Louis II, Landgrave of Hesse, 1438–1471 William II, Landgrave of Hesse, 1469–1509 Philip I, Landgrave of Hesse, 1504–1567 William IV, Landgrave of Hesse-Kassel, 1532–1592 Maurice, Landgrave of Hesse-Kassel, 1572–1632 William V, Landgrave of Hesse-Kassel, 1602–1637 William VI, Landgrave of Hesse-Kassel, 1629–1663 Philip, Landgrave of Hesse-Philippsthal, 1655–1721 William, Landgrave of Hesse-Philippsthal-Barchfeld, 1692–1761 Landgrave Adolf of Hesse-Philippsthal-Barchfeld, 1743–1803 Landgrave Karl of Hesse-Philippsthal-Barchfeld, 1784–1854 Prince Wilhelm of Hesse-Philippsthal-Barchfeld, 1831–1890 Chlodwig, Landgrave of Hesse-Philippsthal-Barchfeld, 1876–1954 Prince Wilhelm of Hesse-Philippsthal-Barchfeld, 1905–1942 Wilhelm, Landgrave of Hesse-Philippsthal-Barchfeld, b.
