The dating of the pieces is complex and so is the history of the various parts. The brooch is the oldest part, judging by the setting and ornament (c.1580-1600).

The necklace is a composite piece. The oldest links are the four on either side of the clasp (four snake links and four smaller links); they are reminiscent of other late sixteenth century chain links of c.1600. The central part of the principal element and the star link to the left are probably somewhat later, c.1630. The scrolls surrounding the central part and the link to the right of it were probably added at the same time as they both lack enamel on the reverse. The remaining two snake-links, the other star link and the border of the principal element are of a later date.

The earrings were created in the nineteenth century.

A 1909 inventory in the Royal Collection, to which the parure has been added at a later date, states that the parure was given by Mary, Queen of Scots to her attendant Mary Seton. Mary Seton was a devoted attendant and friend of Mary, Queen of Scots, who shared many years of her exile. She was an excellent hairdresser whose services the Queen greatly admired

The chain was originally longer; it was a cotiere - a long chain worn by women caught up in the breast. Mary Seton’s descendant, Alexander Seton, 6th Earl of Eglinton (d.1661), removed four snake links and four S-ornaments from the chain on his succession to the earldom in 1612. The remaining sixteen snake links and sixteen white S’s set with rubies were passed to the Hon. Elizabeth Seton when she married William Hay of Drummelzier in 1694. The 1909 inventory states that this part of the chain was recorded in a Hay inventory in 1727.

The remainder of the jewels passed eventually to Alexander Seton’s descendant, Archibald William, 13th Earl of Eglinton (1812-1861). In the nineteenth century, the eight links from the original chain removed by the 6th Earl - four snakes and four S-ornaments - were incorporated into the present Neo-Renaissance necklace. This may have been for the celebrated Eglinton Tournament, held by the 13th Earl at Eglinton Castle in 1839

The parure remained in the possession of the Eglinton family until it was sold, together with the Eglinton family jewels, by the three daughters of the 13th Earl, Egidia, Sybil and Hilda, in 1894 at Christie’s on 22 February 1894 (lot 69). It was acquired by Algernon Borthwick, 1st Baron Glenesk (1830-1908) whose daughter, Lilias Countess Bathurst (d.1965), presented the parure to Queen Mary on the occasion of King George V’s Silver Jubilee in May 1935.