Sir John Henry Seale, 1st Baronet (1780–1844) of Mount Boone in the parish of Townstal near Dartmouth in Devon, was a Whig Member of Parliament for Dartmouth in 1838.[2] He was created a baronet on 31 July 1838.[3] He owned substantial lands in Devon, mainly at Townstal and Mount Boone. Together with the Earl of Morley of Saltram House near Plymouth, he built several bridges in Dartmouth, most notably the Dart crossing.[2] Arthur Howe Holdsworth's, the previous Member of Parliament in Dartmouth, influence over the pocket borough of Dartmouth ceased after the 1832 Reform Act and subsequently he was in competition for that parliamentary seat with John Seale, who won the seat.
The family descended from John Seale (born c. 1512) of St Brelade in Jersey, a descendant of Robert Seale (or Scelle) a gens de bien of St Brelade 1292.[4] In 1720 the 1st Baronet's grandfather John Seale, purchased the estate of Mount Boone near Dartmouth. The latter's great-grandfather was John Seale, Constable of St Brelade 1644-51, the son of John Seale, Constable of St Brelade 1615-21.[5]