Recorded as Slark and Slarke, this is an English surname. It is believed to be a dialectal variant of Slack which is either a topographical name for someone who lived in a shallow valley, or a locational name from one of the many places called Slack, for example Slack, near Stainland, and near Hebden Bridge in West Yorkshire, deriving from the Olde Norse "slakki" meaning "valley". It may also be a nickname for a carefree person, deriving from the Middle English "slack", Olde English pre 7th Century "slaec" meaning "careless". The surname dates back to the late 12th Century (see below). Further recordings include Thomas del Slakk (1275), Court Rolls of the Manor of Wakefield, and Thomas Slak (1359), Calendar of Letter Books of the city of London. Parish registers show Elizabeth, the daughter of Elias Slarke, who was christened on July 14th 1644 in St. Olave's Church, Southwark, London, and John Slark who married Hannah Webb on August 16th 1688 in St. James' Church, Duke's Place, London. The first recorded spelling of the family name is shown to be that of Gerebod le Slac which was dated 1195, in the "Pipe Rolls of Lincolnshire", during the reign of King Richard 1st, known as "The Lionheart", 1189 - 1199. 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.