This Doulton, Lambeth Persian ware vase is almost without doubt by Harry Simeon born 1871 - died 1953 (designer) or William Rowe who collaborated with him.
They both worked on the new Persian Ware introduced by Doulton on the back of William De Morgan’s highly successful Isnik inspired designs of a couple of decades or so earlier. Introduced by Doulton at the Lambeth works around 1919/1920. Harry Simeon left in 1936.
They are probably amongst some of Doulton's most beautiful “new” art wares introduced at the turn of the 19th Century to get in the modern groove.
This fine and very rare, early example is hand painted on a pottery body - rather than the later stoneware (somewhat impersonal and mass-produced to my mind and eye) vases and chargers.
These early examples were only produced in small quantities due to the amount of work which went into them and are extremely sought after.
For an identical shaped vase go to the Victoria and Albert Museum online gallery: