The names that usually float to the top are Sir William Jones, the Grimm Brothers, and Ferdinand de Saussure. Many others contributed as well, but these figures mark special milestones in the development of linguistics. Some online sources to get one started.
Overviews:
a chapter on “The History of Linguistics” by Lyle Campbell
The Indo-Europeans and Historical Linguistics
Ran Levi, “The Indo-European Language”
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Sir William Jones’ (1746–1794) - initiated modern historical linguistics by noting similarities between Sanskrit, Greek and Latin in a lecture to the Asiatic Society in 1786. That led to the PIE theory.
Franklin Edgerton on William Jones
As Edgerton writes, “…the
specific fact that Sanskrit resembles Greek and Latin had been seen
before. But no one before Jones had drawn the inference that these
resemblances must be explained by the assumption of common descent from a
hypothetical earlier language ‘ which, perhaps, no longer exists.’ At
this moment modern comparative grammar was born.”
See also
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The Brothers Grimm - Ludwig ((1785–1863) and Wilhelm Carl (1786-1859) theorized on how the sound of consonants changed.
Linguistics and the Brothers Grimm
Winfred Lehman, “Textlinguistics and Three Literary Texts,”
On PIE (proto-Indo-European)
==
Ferdinand de Saussure (1857–1913), founder of Structural Linguistics, lectured on Sanskrit and Indo-European languages at the University of Geneva, who created a position in Sanskrit for him.
On de Saussure, see
Ernst Koerner’s 1971 dissertation, “Ferdinand de Saussure: Origin and Development of his Linguistic Theory in Western Studies of Language.”
a searchable PDF — search for “sanskrit” (without the quotation marks).
Pieter A.M. Seuren, “Saussure and his intellectual environment”
Good luck,
Dan Lusthaus