1.1.4.3.1.Friedrich Hermann von Schönburg auf Wesel, 1640 Graf von Schönburg [Schomberg], 1663 Conde de Mertola, Comte de Courbet et de Vitry-en-Brie, 1689 Duke of Schomberg, Marquess of Harwich, Earl of Brentford and Baron Teyes [with remainder of British titles to 5th son, then 3rd son, then other sons] (Heidelberg 6 Dec 1615-k.a.the Boyne 1 Jul 1690); m.1st 30 Apr 1638 Johanna Elisabeth von Schönburg auf Wesel (above); m.2nd 14 Apr 1669 Susanne d’Aumale (d.Dohna Palace, Berlin 1688)
1.1.4.3.1.1.Otto (Geisenheim 15 Mar 1639-k.a.Valenciennes 1656)
1.1.4.3.1.2.Friedrich Gf von Schönburg, Conde de Mertola (Oberwesel 14 Mar 1640-Geisenheim 5 Dec 1700); m.1st (div) Katharina Ernestina von Bocholtz (d.30 Aug 1716); m.2nd 1684 Amalie Charlotte Veronika Freiin von Spaen (1661-1731)
1.1.4.3.1.2.1.Maria Wilhelmine Elisabeth; m.1703 Friedrich Graf zu Sayn-Wittgenstein (d.27 Mar 1723)
1.1.4.3.1.3.Meinrad Gf von Schönburg, cr 1691 Duke of Leinster, Earl of Bangor and Baron of Tara, suc 1693 as 3rd Duke of Schomberg (Köln 30 Jun 1641-Hillingdon 5 Jul 1719); m.1st La Rochelle 3 Aug 1667 Barbara Luisa Rizzi; m.2nd 4 Jan 1683 Karoline Elisabeth, Raugräfin (19 Nov 1659-Kensington 28 Jun 1696)
1.1.4.3.1.3.1.Charles Louis, Marquess of Harwich (15 Dec 1683-5 Oct 1713)
1.1.4.3.1.3.2.Caroline (1686/7-18 Jun 1710)
1.1.4.3.1.3.3.Frederica Suzanne, Cdsa de Mertola (1688-7 Aug 1751); m.1st 1715 Robert D’Arcy, 3rd Earl of Holderness (d.20 Jan 1722); m.2nd 18 Jun 1724 Benjamin Mildmay, Earl Fitzwalter (d.29 Feb 1756)
1.1.4.3.1.3.4.Maria (16 Mar 1692-29 Apr 1762); m.1717 Christoph Martin Gf von Degenfeld-Schonburg (d.10 Aug 1762)
1.1.4.3.1.3.5.a child, b.ca May 1695
1.1.4.3.1.4.Heinrich (Hertogenbosch 9 Jul 1643-d.Brussels 1667 of wounds received in action)
1.1.4.3.1.5.Charles Gf von Schönburg, 1690 2nd Duke of Schomberg (Hertogenbosch 5 Aug 1645-Turin 16 Oct 1693)
1.1.4.3.1.5.1.[illegitimate] N Sibourg
1.1.4.3.1.6.Wilhelm (Hertogenbosch 11 Aug 1647- )
Friedrich/Frederick Schomberg (b. 6 Dec. 1615) married firstly 1638 his cousin, Johanna Elizabeth (d. 21 March 1663/64), daughter of his paternal uncle, Henrich Dietrich, Count of Schonberg. Friedrich had five sons, though only two sons survived to adulthood. The overall second son was Meinhardt (b. 30 June 1641) while overall fifth and youngest son was Charles (b. 5 August 1645). Note that Frederick married secondly as well though this marriage bore no issue.
In 1689, he was created Baron Teyes, Earl of Brentford, Marquess of Harwich and Duke of Schomberg [E] all with remainder to his 5th son, Charles, and the heirs male of his body, failing which to his 2nd son, Meinhardt, and the heirs male of his body, failing which to his own heirs male of the body (i.e. the heirs male of the grantee).
Now you asked why was the remainder to the younger (5th) son instead of the elder (2nd) son? It was because Meinhardt (himself a distinguished general like his father) only a short time later (and in anticipation of this) in 1690/91 was be created Baron Tara, Earl of Bangor and Duke of Leinster [I] (the titles were to celebrate his victory following the Battle of the Boyne). To avoid having the two titles merge and remain separate, this is probably why the Dukedom of Schomberg [E] and other titles were given a remainder to the younger son.
Thus, when Friedrich died on 4 July 1690, the Dukedom of Schomberg [E] passed to his younger (5th) son, Charles, who died unmarried on 16 October 1693. The title then passed off course to his brother, Meinhardt. Meinhardt therefore became 3rd Duke of Schomberg [E] and 1st Duke of Leinster [I]. Meinhardt died without surviving male issue on 5 July 1719, when all the titles [E] and [I] became EXTINCT.
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