[1] The first attempt and claim to produce a sulfur iodide were made in 1813 by Bernard Courtois when exploring the properties of his newly discovered element, iodine.

Between 1827 and 1896, more attempts were made to make sulfur iodide by combining the elements; however, all were inconclusive on the existence of the compound or failed.

Later, when thermal analysis was developed, it was shown that when the elements were combined, it only resulted in a mixture, not a compound.

When observing the reaction of very dilute disulfur dichloride in carbon tetrachloride and potassium iodide:[2][3] they observed a color change from yellow to reddish-brown to finally violet, which was assumed to be evidence for the formation of sulfur iodides.

[4][5] Disulfur diiodide is light-sensitive and is soluble in various haloalkanes, such as carbon tetrachloride.