Recorded as Illsley and Illesley, this is an English surname of pre 7th century Anglo-Saxon origins. It is locational from the villages known as today East and West Ilsley in the county of Royal Berkshire. The original settlement was recorded in the Domesday Book of 1086 as "Hildeslei", and as "Illeslai" in 1130, in the Pipe Rolls of Berkshire. The placename is composed of the Olde English personal name "Hild", meaning battle or strife, and the word "leah", meaning a clearing suitable for agriculture. During the Middle Ages from the 12th century, when migration for the purpose of job-seeking was becoming more common, people often used their former village name as a means of identification, resulting in a wide dispersal of the surname. Early examples include those of Thomas Ilsley of Berkshire recorded in the register of students of Oxford University in 1581, and in the Berkshire church registers those of the christenings at Wantage of Margery and Jone, daughters of Richard and Jone IIlesley, on January 24th 1552, and May 28th 1555, respectively; and the christening of Joane Illsley at Compton near Newbury, on September 26th 1571. The family Coat of Arms depicts two black bars gemels, in chief three pellets, on a gold shield. 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.