This is a variation on stem stitch: a line of stem stitch is worked, and then a thread is threaded through each stitch, always in the same direction to give a rope-like effect.  The whipping thread can be the same as the stem stitch thread or a contrasting one.

Whipped stem stitch was certainly in use by the 16th century: it features on a 16th century border fragment of unknown origin and an ecclesiastical panel from the same era made in Switzerland.  It also features on an English band sampler from the following century.

It is also one of the staple stitches in Guimaraes embroidery, a technique which originated in northern Portugal in the 18th century.