This most interesting surname is of Scottish origin, and is a locational name from a place so called in the parish of Bedrule in Roxburghshire, Scotland. This placename is composed of the Scots-Gaelic element "rua", red and the Anglo-Norman French word "castel", castle, fortified building, especially the residence of a feudal lord. Locational surnames were developed when former inhabitants of a place moved to another area usually to seek work, and were best identified by the name of their birthplace. The first recording of the surname dates from the late 13th Century (see below). William de Roucastell had a pension of 20 from King Robert Bruce (1306-1329), according to the Register of the Great Seal of Scotland. Modern variant spellings of the surname include Rowcastle, Rewcassell, Ruecastle and Reucastle. Marion, daughter of Grissell Rewcastle was christened on December 22nd 1670 in Edinburgh, and Robert Rewcastle was an indweller (an inhabitant) in Harwick in 1674, according to the Register of Apprentices of the City of Edinburgh, 1583 - 1755. The first recorded spelling of the family name is shown to be that of William de Rucastel, of the county of Roxburghshire, which was dated 1296, of the county of Roxburghshire, recorded in the "Calendar of Documents relating to Scotland", during the reign of King John Balliol, King of Scotland (1292 - 1296). 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.