This interesting name is of English locational origin from either of two places called "Welby", in Leicestershire recorded "Alebi(e)" in the Domesday book of 1086, and "Oleby" in 1242, in the Book of Fees, and in Lincolnshire, recorded "Wellebi" in the Domesday book. The former place in Leicestershire means "Ali's By", from the Old Norse and Old Danish personal name "Ali", plus the second element "by", an Old Scandinavian element found in English placenames meaning village or homestead. The latter place derives from the Old English "wella" spring, stream and the second element as above, hence a village by a stream, spring. In the surname itself the intrusive "s" in Welsby is a dialectal addition, introduced to make for easier pronunciation. Henry de Welleby recorded in 1332, in the Subsidy Rolls of Warwickshire, while Geoffrey Welby was mentioned in 1395, in the Assize Rolls of Lincolnshire. Henry Welby (d. 1636), entered St. John's college, Cambridge, 1558, and became a recluse in Grub Street, London in mortification at the dissolute and violent character of his brother John 1592, and spent all his means in charity. The first recorded spelling of the family name is shown to be that of Thomas de Wellebi, which was dated 1202, Pipe Rolls of Lincolnshire, during the reign of King John known as "Lackland", 1199 - 1216. 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.