Several sources on the net indicate that name is of English origin. Example below:
Last name: Putnam
SDB Popularity ranking: 3316
This name is of English locational origin from the villages of Puttenham in Hertfordshire or Surrey. The Hertfordshire village is more likely, as it is earlier, being recorded as Puteham in the famous Domesday Book of 1086 and as Putenham in the 1212 Court Rolls of that county. Puttenham in Surrey is first recorded as Puteham in 1199. The name in both cases derives from the Olde English pre 7th Century personal nickname Putta meaning "Kite" (a bird of prey), plus "ham", a homestead. Hence,"Putta's ham". The surname is first recorded at the beginning of the 13th Century, (see below), and has appeared in several local slang forms including Puttnam, Putnam and the dialectally transposed Putman!. Early examples of the surname recordings taken from authentic church registers include Edward Putman or Putnam in the Oxford University Register of 1621, whilst on April 23rd 1753, the marriage of Elizabeth Puttnam and Richard Stevens is recorded in the register of Tring, Hertfordshire. The first recorded spelling of the family name is shown to be that of Ralph de Puteham. which was dated 1205, in the Pipe Rolls of the county of Buckinghamshire. This was during the reign of King John of England, 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.
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