English castles, including Kenilworth, did not play a decisive role during the Wars of the Roses (1455–85), which were fought primarily in the form of pitched battles between the rival factions of the Lancastrians and the Yorkists.[90] With the mental collapse of King Henry VI, Queen Margaret used the Duchy of Lancaster lands in the Midlands, including Kenilworth, as one of her key bases of military support.[91] Margaret removed Henry from London in 1456 for his own safety and until 1461, Henry's court divided almost all its time among Kenilworth, Leicester and Tutbury Castle for the purposes of protection.[92] Kenilworth remained an important Lancastrian stronghold for the rest of the war, often acting as a military balance to the nearby castle of Warwick. With the victory of Henry VII at Bosworth, Kenilworth again received royal attention; Henry visited frequently and had a tennis court constructed at the castle for his use.[4] His son, Henry VIII, decided that Kenilworth should be maintained as a royal castle.[87] He abandoned the Pleasance and had part of the timber construction moved into the base court of the castle.[87]