Short answers, pulled from the story.
Hervey le Breton was the first Earl of Wiltshire and the title was created in 1139. Hervey le Breton forfeited his title within two years of receiving it because he lost his English lands during the Anarchy.
The Earl of Wiltshire title reverted to the Crown with the death of Margaret Longespée in October 1348. Margaret Longespée was the great-granddaughter of Patrick of Salisbury and the title became vacant after her death.
William le Scrope was executed during the events leading to the deposition of Richard II by Henry IV in 1397. The House of Lords rejected a claim to the title in 1859, confirming that the second creation of the Earl of Wiltshire had truly died with William.
James Butler fought on the Lancastrian side at the Battle of Towton and was executed and posthumously attainted for his loyalty to a losing cause. The title of Earl of Wiltshire was forfeit in 1461, marking the end of his line's claim to the earldom.
Thomas Boleyn's line became extinct when he outlived his son and had no other male heirs upon his death. Anne Boleyn's execution in 1536 marked the end of their political power and the title became vacant.
William Paulet was the first Earl of Wiltshire of the seventh creation in 1550 and his descendants continue to hold both titles to this day. The title of Earl of Wiltshire is now used as the courtesy title of Lord Winchester's eldest son and heir.