Complex sentence: She married first Henry of Nonant (Novaunt), lord of Totnes, Devonshire (d.s.p.1206); in 1207 she petitioned the crown for the right to marry whom she wished.
Split into simpler sentences: She married first Henry of Nonant (Novaunt), lord of Totnes, Devonshire who died childless in 1206. In 1207, she petitioned the Crown for the right to marry whom she wished.