This very uncommon name is of Cornish origin, and is a variant form of the surname found variously as Trew(h)ella and Trew(h)eela, which is from either of the places called Trewhella in the parish of St. Hilary or Trewhela in the parish of Enoder. The placenames are derived from the Cornish "tre", homestead, settlement, and a derivative of "hwilen", beetle, although this second element has also been thought to be "ughella", highest; thus, "highest homestead" or "homestead infested with beetles". Locational surnames were used particularly as a means of identification by those who left their birthplace to settle elsewhere, and regional dialectal differences in addition to varying standards of literacy subsequently gave rise to variant forms of the original name. In this instance, certainly, there are a great many such variants, ranging from Trewela(r), Treweler and Treweelor, to Trewheeler, Trewilla, Trewler, Trol(l)er and Trowler. Examples from Church Registers include: the christening of Henry, son of John Troloer, at Wendron, Cornwall, on July 15th 1691; the marriage of Daniel Trowler and Mary Lowde on November 24th 1734, at Newton St. Cyres, Devonshire; and the marriage of Rachel Trowler and William Boyce at Bath Abbey, Somerset, on April 7th 1776. The first recorded spelling of the family name is shown to be that of Richard Trewella, which was dated January 15th 1564, witness to the christening of his daughter, Mary, at Redruth, Cornwall, during the reign of Queen Elizabeth 1, 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.