This Cornish surname is locational, and is recorded in several spellings including Treleaven, Treleven, Treliveing, Trelevan, as examples. It also has multiple sources of origination since there are a number of places even down to single farms in Cornwall whose names derive from the ancient 'tre leven', meaning 'the house or homestead on the level land', or in some cases 'the homes of Leven', with Leven being an original personal name, pre-dating the introduction of surnames. The earliest surviving church registers in Cornwall date from the year 1600, and this name in its various spellings was amongst the very first to be registered. There is little doubt that amongst the early land charters of Cornwall this surname will be recorded, but we do not have the necessary immediate access to these (usually) unpublished records. It is said that the surname has its epicentre in Mid Cornwall, and specifically Lanlivery Rural Parish, and this is so, but it is also well recorded through most of the county. Early examples of the recordings include John Treleven of Padstow on May 9th 1605, Grace Trelevan of Lostwithiel on September 21st 1610, and Agnes Treleaven of Lanlivery Rural parish, the daughter of Thomas Treleaven, christened there on September 2nd 1621. Catherine Treleven was christened at Botus Fleming on October 13th 1664, and Robart Treliveing was a witness at Landulph church, on March 2nd 1696. The first recorded spelling of the family name is shown to be that of Thomas Treleven, which was dated March 3rd 1602, a witness at Lanlivery church, Cornwall, during the reign of Queen Elizabeth 1st, known as 'Good Queen Bess', 1558 - 1603. Surnames became necessary when governments introduced personal taxation. In England this was known as Poll Tax. Throughout the centuries, surnames in every country have continued to "develop" often leading to astonishing variants of the original spelling.