Friedrich Wilhelm I, Duke of Saxe-Weimar

Frederick Wilhelm I, Duke of Saxe-Weimar (b. Weimar,25 April 1562 - d. Weimar, 7 July 1602), was a duke of Saxe-Weimar.

He was the eldest son of Johann Wilhelm, Duke of Saxe-Weimar and Dorothea Susanne of Simmern.

At the time of the death of his father (1573) Frederick Wilhelm was still under age; for this, a tutelary government for the duchy was appointed. This was stressed by the Dowager Duchess Dorothea Susanne, because she cannot not prevent, however, in her place theElector Augustus of Saxony -from the Albertine line- was designated as the regent.

In 1586 Frederick Wilhelm was declared an adult and began his independent government over in Saxe-Weimar. Five years later, in 1591, the Elector Christian I of Saxony died and was succeded by his eldest son Christian II. Because the new Elector was still under age, the regency of the Electorate was assigned to Frederick Wilhelm. With the title of Administrator des Sächsischen Kurstaates (Administrator of the Saxonian Electorate) took residence in Torgau, and neglected the government of his duchy. These were led by his younger brother Johann, which had to be taken part -in accordance with the ernestine House Law- anyway in the government.

In 1601 ended the regency in the Electorate of Saxony with the majority of Elector Christian II, and Frederick Wilhelm returned to Saxonia Weimar. Since he however already died one year later, he not left large traces in the history of the duchy.

In Weimar on 5 May 1583 Frederick Wilhelm married firstly with Sofie of Württemberg. They had six children:

1. Dorothea Marie (b. Weimar, 8 May 1584 - d. Weimar, 9 September 1586).
2. Johann Wilhelm (b. Weimar, 30 June 1585 - d. Weimar, 23 January 1587).
3. Frederick (b. Weimar, 26 September 1586 - d. Weimar, 19 January 1587).
4. Dorothea Sofie (b. Weimar, 19 December 1587 - d. Weimar, 10 February 1645), Abbess of Quedlinburg 1618.
5. Anna Marie (b. Weimar, 31 March 1589 - d. Dresden, 15 December 1626).
6. stillborn son (Vacha, 21 July 1590).

In Neuburg on 9 September 1591 Frederick Wilhelm married secondly with Anna Marie of Bavaria-Neuburg. They had six children:

1. Johann Philipp, Duke of Saxe-Altenburg (b. Torgau, 25 January 1597 - d. Altenburg, 1 April 1639).
2. Anna Sofie (b. Torgau, 3 February 1598 - d. Öls, 20 March 1641), married on 4 December 1618 to Duke Karl Frederick of Münsterberg-Öls.
3. Frederick, Duke of Saxe-Altenburg (b. Torgau, 12 February 1599 - killed in battle, 24 October 1625), co-ruler with his brother over the domains in Altenburg (1603-1625).
4. Johann Wilhelm, Duke of Saxe-Altenburg (b. Torgau, 13 April 1600 - d. Lager, near Brieg, 2 December 1632), co-ruler with his brothers over the domains in Altenburg (1603-1632).
5. Dorothea (b. Torgau, 26 June 1601 - d. Altenburg, 10 April 1675), married on 24 June 1633 to Albrecht, Duke of Saxe-Eisenach.
6. Frederick Wilhelm II, Duke of Saxe-Altenburg (b. posthumously, Weimar, 12 February 1603 - d. Altenburg, 22 April 1669).