Who married Amalia of Solms-Braunfels?

Amalia of Solms-Braunfels (31 August 1602 – 8 September 1675) was Princess of Orange by marriage to Frederick Henry, Prince of Orange. She acted as the political adviser of her spouse during his reign, and acted as his de facto deputy and regent during his infirmity from 1640 to 1647. She also served as chair of the regency council during the minority of her grandson William III, Prince of Orange from 1650 until 1672.

Frederick Henry (Dutch: Frederik Hendrik; 29 January 1584 – 14 March 1647) was the sovereign prince of Orange and stadtholder of Holland, Zeeland, Utrecht, Guelders, and Overijssel in the Dutch Republic from his older half-brother's death on 23 April 1625 until his death on 14 March 1647. In the last seven years of his life, he was also the stadtholder of Groningen (1640-1647).

As the leading soldier in the Dutch wars against Spain, his main achievement was the successful Siege of 's-Hertogenbosch in 1629. It was the main Spanish base and a well-fortified city protected by an experienced Spanish garrison and by formidable water defenses. His strategy was the successful neutralization of the threat of inundation of the area around 's-Hertogenbosch' and his capture of the Spanish storehouse at Wesel. The successful sieges under his command earned him the epithet ‘city forcer’ (Dutch: stedendwinger). He was the paternal grandfather of William III, who later became King of England, Scotland & Ireland, through his only surviving son, William II.