Elias Riggs (November 19, 1810 – January 17, 1901) was an American Presbyterian missionary and linguist.

[4][5] During his missionary activities in the Ottoman Empire he contributed greatly to the Bulgarian National Revival.

[4][9] The government and church of newly independent Greece originally opposed Riggs' mission, but later had to accept American and British Protestant activities among Christians other than Greeks.

Riggs took part in negotiations identifying the then actual ethnic delimitation between Greeks and Bulgarians in the Ottoman Empire, resulting in an approximate line drawn between Serres and Edessa in Macedonia north of which the Christian population was recognized as predominantly Bulgarian.

Subsequently, the 1876 Constantinople Conference of the Great Powers confirmed that early delimitation in its more comprehensive definition of ethnic Bulgarian lands as of the late 19th century.